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Diagnostic Trouble Code (DTC) P0171

Fuel Trim System Too Lean

System Description

If the adaptation value threshold is permanently exceeded, the deviation of the adaptive terms enables to detect a slow default coming out. Two time counters (one for the rich side and another one for the lean side) are increased while the lambda controller exceeds the adaptation thresholds. As soon as one of the time counters reaches its maximum value, the error is detected.
The aim of this test is to simulate a failure that would result in exceeding the adaptive terms. Two kinds of failure must be created.
It is thus necessary to determine, for each kind of failure, the limit good and the limit bad. For a given failure, measure the emission threshold until the legal emission thresholds are exceeded.
Note that the problem is due to the emission thresholds required, it is not simple to disturb the system so that the emission thresholds will be exceeded. The tuning has been made thanks to a dedicated calibration but, as such a procedure is not permitted by the regulation, it is necessary to create some material malfunction (fuel pressure regulator, fuel injector, air leakage...).

Conditions for Setting the DTC

Action Taken When the DTC Sets

Conditions for Clearing the MIL/DTC

Diagnostic Aids

Important : After repairs, use the scan tool Fuel Trim Reset function to reset the long-term fuel trim to 128 (0%).

Check for poor O2S or MAP sensor connection at the ECM. Inspect the harness connectors for the following conditions:
Inspect the wiring harness for damage. If the harness appears to be OK, observe the O2S display on the scan tool while moving the connectors and the wiring harness related to the engine harness. A change in the display will indicate the location of the fault.
Check the brake power booster check valve for possible leaks.

DTC P0171 - Fuel Trim System Too Lean

Step Action Value(s) Yes No
1
Perform an Euro On-Board Diagnostic (EOBD) System Check.
Is the system check complete?
-
Go to Step 2
Go to "On-Board Diagnostic System Check"
2
  1. Install the scan tool to the Data Link Connector (DLC).
  2. Turn the ignition ON.
Are any component related Diagnostic Trouble Codes (DTCs) set?
-
Go to
Applicable DTC
table
Go to Step 3
3
With the engine running, operate the vehicle until the LOOP STATUS indicates closed.
Is the Long Term Fuel Trim value below the specified value?
27%
Go to Step 4
Go to Step 5
4
  1. Turn the ignition switch ON, with the engine OFF.
  2. Review the Freeze Frame data and note the parameters.
  3. Operate the vehicle within the Freeze Frame conditions and Conditions for Setting The DTC as noted.
Does the Long Term Fuel Trim value go below the specified value while operating under the specified conditions?
27%
Go to Step 16
Go to Step 5
5
Visually/physically check the following items:
  • Vacuum hoses for splits, kinks and improper connections.
  • Crankcase ventilation oil/air separator for proper installation.
  • Exhaust system for corrosion, leaks, loose or missing hardware.
  • Oxygen sensor (O2S) is installed securely and the pigtail harness is not contacting exhaust manifold or engine.
  • Fuel for excessive water, alcohol, or other contaminants.
  • Engine Control Module (ECM) and sensor grounds are clean, tight, and in their proper locations.
Do any of the above checks isolate a condition requiring repair?
-
Go to Step 7
Go to Step 6
6
  1. Disconnect the Manifold Absolute Pressure (MAP) sensor electrical connector.
  2. Operate the vehicle in Closed Loop while monitoring the Long Term Fuel Trim value.
Is the Long Term Fuel Trim value below the specified value?
27%
Go to Step 15
Go to Step 9
7
  1. Repair the malfunction found in Step 5.
  2. Recheck the Long Term Fuel Trim value while operating the engine.
Is the Long Term Fuel Trim value below the specified value?
27%
Go to Step 8
Go to Step 9
8
Lean condition is not present.
Does a driveability problem exist?
-
Go to "Symptom Diagnosis"
Go to Step 16
9
  1. Visually/physically inspect the following items for vacuum leaks:
    • Intake manifold.
    • Throttle body.
    • Injector O-rings.
  2. Repair any leaks found as necessary.
Is the repair complete?
-
Go to Step 16
Go to Step 16
10
Allow the engine to idle.
Are the Idle Air Control (IAC) counts above the specified value?
5
Go to Step 11
Go to Step 12
11
Check the fuel for excessive water, alcohol, or other contaminants and correct the contaminated fuel condition if present.
Is the repair complete?
-
Go to Step 16
Go to Step 13
12
Check the IAC valve performance. Refer to "DTC P0506 Idle Speed RPM Lower Than Desired Idle Speed" or "DTC P0507 Idle Speed RPM Higher Than Desired Idle Speed" in this section and repair as necessary.
Is the repair complete?
-
Go to Step 16
Go to Step 13
13
  1. Connect a fuel pressure gauge to the fuel system.
  2. Turn the ignition OFF for at least 10 seconds.
  3. Turn the ignition ON, with the engine OFF. The fuel pump will run for approximately 2-3 seconds. It may be necessary to cycle the ignition switch ON more than once to obtain maximum fuel pressure.
  4. Note the fuel pressure with the fuel pump running. The pressure should be within the specified value. When the fuel pump stops, the pressure may vary slightly then hold steady.
Is the fuel pressure steady and does the fuel pressure hold?
241-276 kPa (35-40 psi)
Go to Step 14
Go to "Fuel System Diagnosis"
14
  1. Start and idle the engine at normal operating temperature.
  2. The fuel pressure noted in the above step should drop by the indicated value.
Does the fuel pressure drop by the indicated value?
21-69 kPa (3-10 psi)
Go to "Fuel Injector Balance Test"
Go to "Fuel System Diagnosis"
15
Replace the MAP sensor.
Is the action complete?
-
Go to Step 16
-
16
  1. Using the scan tool, clear the Diagnostic Trouble Codes (DTCs).
  2. Start the engine and idle at normal operating temperature.
  3. Operate the vehicle within the Conditions for setting this DTC as specified in the supporting text.
Does the scan tool indicate that this diagnostic has run and passed?
-
Go to Step 17
Go to Step 2
17
Check if any additional DTCs are set.
Are any DTCs displayed that have not been diagnosed?
-
Go to
applicable DTC
table
System OK

Diagnostic Trouble Code (DTC) P0172

Fuel Trim System Too Rich

System Description

If the adaptation value threshold is permanently exceeded, the deviation of the adaptive terms enables to detect a slow default coming out. Two time counters (one for the rich side and another one for the lean side) are increased while the lambda controller exceeds the adaptation thresholds. As soon as one of the time counters reaches its maximum value, the error is detected.The aim of this test is to simulate a failure that would result in exceeding the adaptive terms. Two kinds of failure must be created.
It is thus necessary to determine, for each kind of failure, the limit good and the limit bad. For a given failure, measure the emission threshold until the legal emission thresholds are exceeded.Note that the problem is due to the emission thresholds required, it is not simple to disturb the system so that the emission thresholds will be exceeded. The tuning has been made thanks to a dedicated calibration but, as such a procedure is not permitted by the regulation, it is necessary to create some material malfunction (fuel pressure regulator, fuel injector, air leakage...).

Conditions for Setting the DTC

Action Taken When the DTC Sets

Conditions for Clearing the MIL/DTC

Diagnostic Aids

Important : After repairs, use the scan tool Fuel Trim Reset function to reset the long-term fuel trim to 128 (0%).

Check for poor connection at the ECM. Inspect the harness connectors for the following conditions:
Inspect the wiring harness for damage. If the harness appears to be OK, observe the O2S display on the scan tool while moving the connectors and the wiring harness related to the engine harness. A change in the display will indicate the location of the fault.
If a DTC P1404 is also set, check the 5 volt reference circuits for a short to voltage.
Check for a restricted exhaust system.
A shorted 5 volt reference circuit may cause a DTC P0172 to set. Check the 5 volt reference sensors for abnormal readings.

DTC P0172 - Fuel Trim System Too Rich

Step Action Value(s) Yes No
1
Perform an Euro On-Board Diagnostic (EOBD) System Check.
Is the system check complete?
-
Go to Step 2
Go to "On-Board Diagnostic System Check"
2
  1. Install the scan tool to the Data Link Connector (DLC).
  2. Turn the ignition ON.
Are any component related Diagnostic Trouble Codes (DTCs) set?
-
Go to
Applicable DTC
table
Go to Step 3
3
With the engine running, operate the vehicle until the LOOP STATUS indicates closed.
Is the Long Term Fuel Trim value above the specified value?
-30%
Go to Step 4
Go to Step 5
4
  1. Turn the ignition switch ON, with the engine OFF.
  2. Review the Freeze Frame data and note the parameters.
  3. Operate the vehicle within the Freeze Frame conditions and Conditions for Setting The DTC as noted.
Does the Long Term Fuel Trim value above the specified value while operating under the specified conditions?
-30%
Go to Step 21
Go to Step 5
5
Visually/physically check the air cleaner filter for excessive dirt or being plugged and repair as needed.
Is the repair complete?
-
Go to Step 21
Go to Step 6
6
Visually/physically check the air intake system for collapsed or restricted and repair as needed.
Is the repair complete?
-
Go to Step 21
Go to Step 7
7
Inspect the throttle body inlet for damaged or foreign objects which may partially block the airflow and repair as needed.
Is the repair complete?
-
Go to Step 21
Go to Step 8
8
  1. Turn the ignition OFF.
  2. Inspect the throttle bore, throttle plate and Idle Air Control (IAC) passages for clocking and foreign objects and repair as needed.
Is the repair complete?
-
Go to Step 21
Go to Step 9
9
Start the engine with the vehicle in park or neutral and A/C off and note the idle quality.
Is a low or unsteady idle being experienced?
-
Go to Step 10
Go to Step 12
10
Idle the engine.
Are the IAC counts below the specified value?
100
Go to Step 12
Go to Step 11
11
  1. Turn the ignition OFF.
  2. Disconnect the Manifold Absolute Pressure (MAP) sensor electrical connector.
  3. Start the engine.
  4. Operate the vehicle in Closed Loop while monitoring the Long Term Fuel Trim value.
Does the Long Term Fuel Trim value increase above the specified value?
-30%
Go to Step 20
Go to Step 12
12
Check the IAC valve performance. Refer to "DTC P0506 Idle Speed RPM Lower Than Desired Idle Speed" or "DTC P0507 Idle Speed RPM Higher Than Desired Idle Speed" in this section and repair as necessary.
Is the repair complete?
-
Go to Step 21
Go to Step 13
13
  1. Disconnect the vacuum hose from the fuel pressure regulator and inspect the hose for the presence of fuel.
  2. If fuel is presence in the vacuum hose, replace the fuel pressure regulator.
Is the repair complete?
-
Go to Step 21
Go to Step 14
14
  1. Turn the ignition ON.
  2. Slowly press the acceleration pedal.
Does the Throttle Position (TP) sensor display increase steady and evenly from its minimum voltage at closed throttle to its maximum voltage at Wide-Open Throttle (WOT).
-
Go to Step 15
Go to Step 19
15
  1. Perform the Fuel System Diagnosis.
  2. If the table isolate a problem, repair as needed.
Is the repair complete?
-
Go to Step 21
Go to Step 16
16
  1. Perform the Evaporative Emission (EVAP) Control System Diagnosis.
  2. If the table isolate a problem, repair as needed.
Is the repair complete?
-
Go to Step 21
Go to Step 17
17
  1. Perform the Fuel Injector Balance Test.
  2. If the table isolate a problem, repair as needed.
Is the repair complete?
-
Go to Step 21
Go to Step 18
18
  1. Remove the Oxygen Sensor (O2S).
  2. Visually/physically inspect the O2S for silicone contamination.
  3. Note: this will be indicated by a powdery white deposit on the portion of the O2S exposed to the exhaust stream.
  4. If contamination is present on the O2S, find the source and repair as needed.
Is the repair complete?
-
Go to Step 21
Go to "Diagnostic Aids"
19
  1. Check the TP sensor mounting screws.
  2. If they are too loose or missing tighten or replace them as needed.
  3. If the screws are OK, replace the TP sensor.
Is the repair complete?
-
Go to Step 21
-
20
  1. Turn the ignition OFF.
  2. Replace the MAP sensor.
Is the repair complete?
-
Go to Step 21
-
21
  1. Using the scan tool, clear the Diagnostic Trouble Codes (DTCs).
  2. Start the engine and idle at normal operating temperature.
  3. Operate the vehicle within the Conditions for setting this DTC as specified in the supporting text.
Does the scan tool indicate that this diagnostic has run and passed?
-
Go to Step 21
Go to Step 2
22
Check if any additional DTCs are set.
Are any DTCs displayed that have not been diagnosed?
-
Go to
applicable DTC
table
System OK

M3C11F14
Display graphicTranslations of text in graphics


Diagnostic Trouble Code (DTC) P0222

Main Throttle Idle Actuator (MTIA) Low Voltage

Circuit Description

The aim of the MTIA (Main Throttle Idle Actuator) is to control the idle speed with the throttle body itself. The throttle is motorized for low opening angle (05, 22.55). The characteristics of the air flow are not the same for low and high opening angles. As a matter of fact, the gradient of the mass air flow function of TPS is lower for small angles that permits to be more precise during the idle speed control. Out of idle speed the throttle is actuated mechanically by a classical bowdencable.
The throttle position sensor (TPS) provides a voltage signal that changes in relation to the throttle plate angle. The signal voltage will vary from about nearly 5.0 V at idle to about 0.2 V to 0.4 V at wide open throttle. The TPS is one of the most important inputs used by the ECM for fuel control and other functions such as idle, wide open throttle, deceleration enleanment, and acceleration enrichment.

Conditions for Setting the DTC

Action Taken When the DTC Sets

Conditions for Clearing the MIL/DTC

Diagnostic Aids

An Intermittent problem may be caused by a poor connection, rubbed through wire insulation, or wire that is broken inside the insulation.
Any circuitry, that is suspected as causing the complaint, should be thoroughly checked for the following conditions.

DTC P0222 - Main Throttle Idle Actuator (MTIA) Low Voltage

Step Action Value(s) Yes No
1
Perform an Euro On-Board Diagnostic (EOBD) System Check.
Is the system check complete?
-
Go to Step 2
Go to "On-Board Diagnostic System Check"
2
  1. Connect the scan tool to the DLC.
  2. Turn the ignition switch to ON.
  3. Press the accelerator pedal while watching TPS for smooth changes in the voltage.
Does the scan tool show the TPS voltage change smoothly within the value specified?
0.3V-4.8V
Go to "Diagnostic Aids"
Go to Step 3
3
  1. Turn the ignition switch to LOCK.
  2. Disconnect the MTIA connector.
  3. Measure the voltage between terminal 2 and 1.
Does the voltage measure within the value specified?
4.8-5.0V
Go to Step 4
Go to Step 5
4
Connect a fused jumper between the MTIA connector terminal 2 and terminal 3.
Does the scan tool show the TPS voltage above value specified?
More than
4.8-5.0V
Go to Step 10
Go to Step 8
5
Measure the voltage between the MTIA connector 2 and ground.
Does the voltage measure within the value specified?
Below 5.0V
Go to Step 6
Go to Step 7
6
  1. Turn the ignition switch to LOCK.
  2. Disconnect the engine control module(ECM).
  3. Check for a short to ground in the wire between the MTIA connector 1 and ECM connector 62.
Is the problem found?
-
Go to Step 9
Go to Step 11
7
  1. Turn the ignition switch to LOCK.
  2. Check for a short to ground in the wire between the MTIA connector 2 and ECM connector 61.
Is the problem found?
-
Go to Step 9
Go to Step 11
8
  1. Turn the ignition switch to LOCK.
  2. Check for a short to ground in the wire between the MTIA connector 3 and ECM connector 55.
Is the problem found?
-
Go to Step 9
Go to Step 11
9
  1. Repair the wire or the connector terminal as needed.
  2. Clear any DTCs from ECM.
  3. Perform the Diagnostic System Check.
Is the repair complete?
-
System OK
-
10
  1. Replace the throttle body assembly.
  2. Clear any DTCs from ECM.
  3. Perform the Diagnostic System Check.
Is the repair complete?
-
System OK
-
11
  1. Ignition OFF.
  2. Replace the ECM.
  3. Perform the Diagnostic System Check.
Is the repair complete?
-
Go to Step 12
-
12
Check if any additional DTCs are set.
Are any DTCs displayed that have not been diagnosed?
-
Go to
applicable DTC
table
System OK

M3C11F14
Display graphicTranslations of text in graphics


Diagnostic Trouble Code (DTC) P0223

Main Throttle Idle Actuator (MTIA) High Voltage

Circuit Description

The aim of the MTIA (Main Throttle Idle Actuator) is to control the idle speed with the throttle body itself. The throttle is motorized for low opening angle (05, 22.55). The characteristics of the air flow are not the same for low and high opening angles. As a matter of fact, the gradient of the mass air flow function of TPS is lower for small angles that permits to be more precise during the idle speed control. Out of idle speed the throttle is actuated mechanically by a classical bowdencable.
The throttle position sensor (TPS) provides a voltage signal that changes in relation to the throttle plate angle. The signal voltage will vary from about nearly 5.0 V at idle to about 0.2 V to 0.4 V at wide open throttle. The TPS is one of the most important inputs used by the ECM for fuel control and other functions such as idle, wide open throttle, deceleration enleanment, and acceleration enrichment.

Conditions for Setting the DTC

Action Taken When the DTC Sets

Conditions for Clearing the MIL/DTC

Diagnostic Aids

An Intermittent problem may be caused by a poor connection, rubbed through wire insulation, or wire that is broken inside the insulation.
Any circuitry, that is suspected as causing the complaint, should be thoroughly checked for the following conditions.

DTC P0223 - Main Throttle Idle Actuator (MTIA) High Voltage

Step Action Value(s) Yes No
1
Perform an Euro On-Board Diagnostic (EOBD) System Check.
Is the system check complete?
-
Go to Step 2
Go to "On-Board Diagnostic System Check"
2
  1. Connect the scan tool to the DLC.
  2. Turn the ignition switch to ON.
  3. Press the accelerator pedal while watching TPS for smooth changes in the voltage.
Does the scan tool show the TPS voltage change smoothly within the value specified?
0.3V-4.8V
Go to "Diagnostic Aids"
Go to Step 3
3
  1. Turn the ignition switch to LOCK.
  2. Disconnect the MTIA connector.
  3. Measure the voltage between terminal 2 and 1.
Does the voltage measure within the value specified?
4.8-5.0V
Go to Step 4
Go to Step 5
4
Connect a fused jumper between the MTIA connector terminal 2 and terminal 3.
Does the scan tool show the TPS voltage above value specified?
More than
4.8-5.0V
Go to Step 10
Go to Step 8
5
Measure the voltage between the MTIA connector 2 and ground.
Does the voltage measure within the value specified?
Below 5.0V
Go to Step 6
Go to Step 7
6
  1. Turn the ignition switch to LOCK.
  2. Disconnect the engine control module(ECM).
  3. Check for an open or short to battery voltage in the wire between the MTIA connector 1 and ECM connector 62.
Is the problem found?
-
Go to Step 9
Go to Step 11
7
  1. Turn the ignition switch to LOCK.
  2. Check for an open or short to battery voltage in the wire between the MTIA connector 2 and ECM connector 61.
Is the problem found?
-
Go to Step 9
Go to Step 11
8
  1. Turn the ignition switch to LOCK.
  2. Check for an open or short to battery voltage in the wire between the MTIA connector 3 and ECM connector 55.
Is the problem found?
-
Go to Step 9
Go to Step 11
9
  1. Repair the wire or the connector terminal as needed.
  2. Clear any DTCs from ECM.
  3. Perform the Diagnostic System Check.
Is the repair complete?
-
System OK
-
10
  1. Replace the throttle body assembly.
  2. Clear any DTCs from ECM.
  3. Perform the Diagnostic System Check.
Is the repair complete?
-
System OK
-
11
  1. Ignition OFF.
  2. Replace the ECM.
  3. Perform the Diagnostic System Check.
Is the repair complete?
-
Go to Step 12
-
12
Check if any additional DTCs are set.
Are any DTCs displayed that have not been diagnosed?
-
Go to
applicable DTC
table
System OK

M5C11F05
Display graphicTranslations of text in graphics


Diagnostic Trouble Code (DTC) P1230

Fuel Pump Relay Low Voltage

Circuit Description

When the ignition switch is turned ON, the ECM will activate the fuel pump relay and run the in-tank fuel pump.
The fuel pump will operate as long as the engine is cranking or running and the ECM is receiving ignition reference pulses.

Conditions for Setting the DTC

Action Taken When the DTC Sets

Conditions for Clearing the MIL/DTC

Diagnostic Aids

An Intermittent problem may be caused by a poor connection, rubbed through wire insulation, or wire that is broken inside the insulation.
Any circuitry, that is suspected as causing the complaint, should be thoroughly checked for the following conditions.

DTC P1230 - Fuel Pump Relay Low Voltage

Step Action Value(s) Yes No
1
Perform an Euro On-Board Diagnostic (EOBD) System Check.
Is the system check complete?
-
Go to Step 2
Go to "On-Board Diagnostic System Check"
2
  1. Turn the ignition switch to LOCK for 10 seconds.
  2. Turn the Turn the ignition switch to ON.
  3. Listen for in-tank fuel pump operation.
Does the fuel pump operate?
2.55 seconds
Go to "Diagnostic Aids"
Go to Step 3
3
  1. Turn the ignition switch to ON.
  2. Disconnect the fuel pump relay.
  3. Connect a test light between the fuel pump relay connector terminal 85 and ground.
  4. Turn the Turn the ignition switch to ON.
Is the test light ON?
-
Go to Step 4
Go to Step 10
4
  1. Turn the ignition switch to ON.
  2. Disconnect the fuel pump relay.
  3. Connect a test light between the fuel pump relay connector terminal 86 and B+.
  4. Turn the Turn the ignition switch to ON.
Is the test light ON?
-
Go to Step 5
Go to Step 9
5
  1. Turn the ignition switch to LOCK.
  2. Connect a test light between the fuel pump relay connector terminal 30 and ground.
Is the test light ON?
-
Go to Step 6
Go to Step 8
6
Check for short to ground in the wire between the fuel pump relay connector terminal 87 and fuel pump connector.
Is the problem found?
-
Go to Step 7
Go to Step 8
7
  1. Repair the wire between the fuel pump relay connector terminal 87 and fuel pump connector terminal 3.
  2. Install the fuel pump relay.
  3. Turn the engine OFF for 10 seconds.
  4. Clear any DTCs from ECM.
  5. Turn the ignition switch to ON.
Does the fuel pump operate?
2.55 seconds
Go to Step 14
-
8
  1. Replace the fuel pump relay.
  2. Turn the ignition OFF for 10 seconds.
  3. Clear any DTCs from ECM.
  4. Turn the Turn the ignition switch to ON.
Does the fuel pump operate?
2.55 seconds
Go to Step 14
Go to Step 9
9
Check for a short to ground wire between the fuel pump relay connector terminal 86 and the ignition after key ON 1(IGN 1).
Is the problem found?
-
Go to Step 11
Go to Step 10
10
Check for a short to ground wire between the fuel pump relay connector terminal 85 and the ECM connector terminal 6.
Is the problem found?
-
Go to Step 12
Go to Step 13
11
  1. Repair the wire between the fuel pump relay connector terminal 86 and the ignition key ON (IGN1).
  2. Install the fuel pump relay.
  3. Turn the ignition OFF for 10 seconds.
  4. Clear any DTCs from ECM.
  5. Turn the ignition switch to ON.
Does the fuel pump operate?
2.55 seconds
System OK
Go to Step 13
12
  1. Repair the wire between the fuel pump relay connector terminal 85 and the ECM connector terminal 6.
  2. Install the fuel pump relay.
  3. Turn the ignition OFF for 10 seconds.
  4. Clear any DTCs from ECM.
  5. Turn the ignition switch to ON.
Does the fuel pump operate?
2.55 seconds
System OK
Go to Step 13
13
  1. Replace the ECM.
  2. Turn the ignition OFF for 10 seconds.
  3. Clear any DTCs from ECM.
  4. Turn the ignition switch to ON.
Does the fuel pump operate?
2.55 seconds
System OK
Go to Step 14
14
  1. Using the scan tool, clear the DTCs.
  2. Start the engine and idle at normal operating temperature.
  3. Operate the vehicle within the conditions for setting this DTC ad specified in the supporting text.
Does the scan tool indicate that this diagnostic has run and passed?
-
Go to Step 15
Go to Step 2
15
Check if any additional DTCs are set.
Are any DTCs displayed that have not been diagnosed?
-
Go to
applicable DTC
table
System OK

M5C11F05
Display graphicTranslations of text in graphics


Diagnostic Trouble Code (DTC) P1231

Fuel Pump Relay High Voltage

Circuit Description

When the ignition switch is turned ON, the ECM will activate the fuel pump relay and run the in-tank fuel pump.
The fuel pump will operate as long as the engine is cranking or running and the ECM is receiving ignition reference pulses.

Conditions for Setting the DTC

Action Taken When the DTC Sets

Conditions for Clearing the MIL/DTC

Diagnostic Aids

An Intermittent problem may be caused by a poor connection, rubbed through wire insulation, or wire that is broken inside the insulation.
Any circuitry, that is suspected as causing the complaint, should be thoroughly checked for the following conditions.

DTC P1231 - Fuel Pump Relay High Voltage

Step Action Value(s) Yes No
1
Perform an Euro On-Board Diagnostic (EOBD) System Check.
Is the system check complete?
-
Go to Step 2
Go to "On-Board Diagnostic System Check"
2
  1. Turn the ignition switch to LOCK for 10 seconds.
  2. Turn the Turn the ignition switch to ON.
  3. Listen for in-tank fuel pump operation.
Does the fuel pump operate?
2.55 seconds
Go to "Diagnostic Aids"
Go to Step 3
3
Check for short to battery voltage or low voltage in the wire between the fuel pump relay connector terminal 87 and fuel pump connector 3.
Is the problem found?
-
Go to Step 7
Go to Step 5
4
  1. Repair the wire between the fuel pump relay connector terminal 87 and fuel pump connector terminal 3.
  2. Install the fuel pump relay.
  3. Turn the engine OFF for 10 seconds.
  4. Clear any DTCs from ECM.
  5. Turn the ignition switch to ON.
Does the fuel pump operate?
2.55 seconds
Go to Step 11
-
5
  1. Replace the fuel pump relay.
  2. Turn the ignition OFF for 10 seconds.
  3. Clear any DTCs from ECM.
  4. Turn the Turn the ignition switch to ON.
Does the fuel pump operate?
2.55 seconds
Go to Step 11
Go to Step 6
6
Check for short to battery voltage wire between the fuel pump relay connector terminal 86 and the ignition after key ON 1(IGN 1).
Is the problem found?
-
Go to Step 8
Go to Step 7
7
Check for an open wire between the fuel pump relay connector terminal 85 and the ECM connector terminal 6.
Is the problem found?
-
Go to Step 9
Go to Step 10
8
  1. Repair the wire between the fuel pump relay connector terminal 86 and the ignition key ON (IGN1).
  2. Install the fuel pump relay.
  3. Turn the ignition OFF for 10 seconds.
  4. Clear any DTCs from ECM.
  5. Turn the ignition switch to ON.
Does the fuel pump operate?
2.55 seconds
System OK
Go to Step 10
9
  1. Repair the wire between the fuel pump relay connector terminal 85 and the ECM connector terminal 6.
  2. Install the fuel pump relay.
  3. Turn the ignition OFF for 10 seconds.
  4. Clear any DTCs from ECM.
  5. Turn the ignition switch to ON.
Does the fuel pump operate?
2.55 seconds
System OK
Go to Step 10
10
  1. Replace the ECM.
  2. Turn the ignition OFF for 10 seconds.
  3. Clear any DTCs from ECM.
  4. Turn the ignition switch to ON.
Does the fuel pump operate?
2.55 seconds
System OK
Go to Step 11
11
  1. Using the scan tool, clear the DTCs.
  2. Start the engine and idle at normal operating temperature.
  3. Operate the vehicle within the conditions for setting this DTC ad specified in the supporting text.
Does the scan tool indicate that this diagnostic has run and passed?
-
Go to Step 12
Go to Step 2
12
Check if any additional DTCs are set.
Are any DTCs displayed that have not been diagnosed?
-
Go to
applicable DTC
table
System OK

M3C11F19
Display graphicTranslations of text in graphics


Diagnostic Trouble Code (DTC) P0261

Injector 1 Low Voltage

Circuit Description

The transaxle control module(TCM)/engine control module (ECM) has four individual injector driver circuits, each of which controls an injector. When a driver circuit is grounded by the ECM, the injector is activated. The ECM monitors the current in each driver circuit. The ECM measures a voltage drop through a fixed resistor and controls it. The voltage on each driver is monitored to detect a fault. If the voltage is not what the ECM expects to monitor on the circuit, a Diagnostic Trouble Code (DTC) is set. This DTC detects a low voltage and/or an open circuit and high voltage conditions for low-side drive injector outputs.

Conditions for Setting the DTC

Action Taken When the DTC Sets

Conditions for Clearing the MIL/DTC

Diagnostic Aids

An injector 4river circuit that is open or shorted to voltage will causes a DTC P0261 to set. It will also cause a misfire due to an inoperative injector. A misfire DTC should also be set indicating which injector is inoperative.
Long-term and short-terms fuel trims that are excessively high or low are a good indication that an injector is malfunctioning. Refer to "Fuel Injector Balance Test" in this section to check for malfunctioning injectors.
The injector resistance tested at the ECM connection is slightly more than it tested directly at the injector because it includes resistance of the harness wires. The normal value is about 13.5Ω.

DTC P0261 - Injector 1 Low Voltage

Step Action Value(s) Yes No
1
Perform an Euro On-Board Diagnostic (EOBD) System Check.
Is the system check complete?
-
Go to Step 2
Go to "On-Board Diagnostic System Check"
2
With the engine start?
-
Go to Step 3
Go to "Engine Cranks But Will Not Run"
3
  1. Install a scan tool and clear the Diagnostic Trouble Codes (DTCs).
  2. Idle the engine for one minuet.
Does DTC P0261 reset?
-
Go to Step 5
Go to Step 4
4
  1. Review the Freeze Frame data with the ignition ON and the engine OFF and note the parameters.
  2. Operate the vehicle within the Freeze Frame conditions as notes.
Does DTC P0261 reset?
-
Go to Step 5
Go to "Diagnostic Aids"
5
  1. Turn the ignition switch to LOCK.
  2. Check for short to ground in the wire between the injector 1 connector terminal 1 and ECM connector terminal 59.
Is the problem found?
-
Go to Step 7
Go to Step 6
6
  1. Turn the ignition switch to LOCK.
  2. Check for short to ground in the wire between the injector 1 connector terminal 2 and battery positive.
Is the problem found?
-
Go to Step 7
Go to Step 8
7
  1. Repair the wire or the connector terminal as needed.
  2. Clear any DTCs from ECM.
  3. Perform the Diagnostic System Check.
Is the repair complete?
-
System OK
-
8
  1. Replace the injector valve.
  2. Clear any DTCs from ECM.
  3. Perform the Diagnostic System Check.
Is the repair complete?
-
Go to Step 9
System OK
9
  1. Turn the ignition switch to LOCK.
  2. Replace the ECM.
  3. Perform the Diagnostic System Check.
Does DTC P0261 reset?
-
Go to Step 10
-
10
Check if any additional DTCs are set.
Are any DTCs displaced that have not been diagnosed?
-
Go to
applicable DTC
table
System OK

M3C11F19
Display graphicTranslations of text in graphics


Diagnostic Trouble Code (DTC) P0262

Injector 1 High Voltage

Circuit Description

The transaxle control module(TCM)/engine control module (ECM) has four individual injector driver circuits, each of which controls an injector. When a driver circuit is grounded by the ECM, the injector is activated. The ECM monitors the current in each driver circuit. The ECM measures a voltage drop through a fixed resistor and controls it. The voltage on each driver is monitored to detect a fault. If the voltage is not what the ECM expects to monitor on the circuit, a Diagnostic Trouble Code (DTC) is set. This DTC detects a low voltage and/or an open circuit and high voltage conditions for low-side drive injector outputs.

Conditions for Setting the DTC

Action Taken When the DTC Sets

Conditions for Clearing the MIL/DTC

Diagnostic Aids

An injector 4river circuit that is open or shorted to voltage will causes a DTC P0262 to set. It will also cause a misfire due to an inoperative injector. A misfire DTC should also be set indicating which injector is inoperative.
Long-term and short-terms fuel trims that are excessively high or low are a good indication that an injector is malfunctioning. Refer to "Fuel Injector Balance Test" in this section to check for malfunctioning injectors.
The injector resistance tested at the ECM connection is slightly more than it tested directly at the injector because it includes resistance of the harness wires. The normal value is about 13.5Ω.

DTC P0262 - Injector 1 High Voltage

Step Action Value(s) Yes No
1
Perform an Euro On-Board Diagnostic (EOBD) System Check.
Is the system check complete?
-
Go to Step 2
Go to "On-Board Diagnostic System Check"
2
With the engine start?
-
Go to Step 3
Go to "Engine Cranks But Will Not Run"
3
  1. Install a scan tool and clear the Diagnostic Trouble Codes (DTCs).
  2. Idle the engine for one minuet.
Does DTC P0262 reset?
-
Go to Step 5
Go to Step 4
4
  1. Review the Freeze Frame data with the ignition ON and the engine OFF and note the parameters.
  2. Operate the vehicle within the Freeze Frame conditions as notes.
Does DTC P0262 reset?
-
Go to Step 5
Go to "Diagnostic Aids"
5
  1. Turn the ignition switch to LOCK.
  2. Check for an open or short to battery voltage in the wire between the injector 1 connector terminal 1 and ECM connector terminal 59.
Is the problem found?
-
Go to Step 7
Go to Step 6
6
  1. Turn the ignition switch to LOCK.
  2. Check for short to battery voltage in the wire between the injector 1 connector terminal 2.
Is the problem found?
-
Go to Step 7
Go to Step 8
7
  1. Repair the wire or the connector terminal as needed.
  2. Clear any DTCs from ECM.
  3. Perform the Diagnostic System Check.
Is the repair complete?
-
System OK
-
8
  1. Replace the injector valve.
  2. Clear any DTCs from ECM.
  3. Perform the Diagnostic System Check.
Does DTC P0262 reset?
-
Go to Step 9
System OK
9
  1. Turn the ignition switch to LOCK.
  2. Replace the ECM.
  3. Perform the Diagnostic System Check.
Is the repair complete?
-
Go to Step 10
-
10
Check if any additional DTCs are set.
Are any DTCs displaced that have not been diagnosed?
-
Go to
applicable DTC
table
System OK


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