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1.8 LV6 Supercharger ECU DTCs and P0115 Stored in the Factory PCM - kw appearance DTC fit hesitate idle lamp light low MIL misfire no performance PCM power rough surge

Subject:1.8 LV6 Supercharger ECU DTCs and P0115 Stored in the Factory PCM

Models:.



When servicing the vehicle with the VIN you entered, the following diagnosis might be helpful if the vehicle exhibits the described symptoms.

Condition/Concern:

Diagnostic codes not covered in the supercharger installation package.

Recommendation/Instructions:

Fail Safe Monitoring of TRD Supercharger System: The supercharger ECU has a monitoring system much like the factory system that will illuminate the MIL lamp if various unsafe engine conditions exist. This monitoring system will set the factory DTC P0115 (Engine Coolant Circuit Malfunction) to alert the driver that there is a problem with the system and the vehicle should be taken to the dealership for inspection. If the Factory ECM shows a P0115 and there is no problem found, check the supercharger ECU TRD module for DTCS. There is a small white 6 pin connector which is used for diagnosis. The supercharger ECU interfaces as an OBD-I system. Connect a test light lead into Pin 4 of the small white 6 pin connector and read the flash pattern to determine the problem area as outlined below:

Switch the ignition key to the (ON) position, which will extract the OBD1 type codes from the supercharger ECU.

21 NE (Crank Sensor) Fault in Wire Connection.

Fault in Crank Sensor.

Fault should appear on factory hand held diagnostic tester.

Refer to GM Service Manual. Conditions for setting DTC 21:

  1. Engine speed zero and mass air flow sensor not faulted and indicating greater than 5 g/s
  2. Or engine speed greater than 8000 RPM

23VG (Mass Air Flow In) Fault in Wire Connection.

Fault in Mass Air Sensor.

Fault should appear on factory hand held diagnostic tester.

Refer to GM Service Manual for MAF Diagnosis.

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24VG (Mass Air Flow Out) Fault in Wire Connection.

Fault in Mass Air Sensor.

Fault should appear on factory hand held diagnostic tester.

Refer to GM Service Manual for MAF Diagnosis.

Fault in supercharger ECU Output Circuit.

Conditions for setting DTC 24:

1. Mass air flow sensor voltage lower than 0.075V

2. Or mass air flow sensor voltage higher than 6.0V

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25VTA (Throttle Angle) Fault in Wire Connection.

Fault in TPS Sensor.

Fault should appear on factory hand held diagnostic tester.

Refer to GM Service Manual for MAF Diagnosis.

Conditions for setting DTC 25:

1. Throttle position sensor voltage lower than 0.025V

2. Or throttle position sensor voltage higher than 4.975V

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26THA (Air Temp.) Fault in Wire Connection.

Fault in Mass Air Sensor.

Fault should appear on factory hand held diagnostic tester.

IAT reading may be erratic on scan data. This is normal.

Refer to GM Service Manual for MAF Diagnosis.

Conditions for setting DTC 26:

1. Inlet air temperature sensor voltage lower than 0.025V

2. Or inlet air temperature sensor voltage higher than 4.957V

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27ECT (Engine Coolant Temp.) Fault in Wire Connection.

Fault in ECT Sensor.

Fault should appear on factory hand held diagnostic tester.

Refer to GM Service Manual for MAF Diagnosis.

Conditions for setting DTC 27:

1. Engine temperature sensor voltage lower than 0.025V

2. Or engine temperature sensor fvoltage higher than 4.975V

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31OX1 (Oxygen Sensor 1) Fault in Wire Connection.

Fault in Sensor. Refer to GM Service Manual for MAF diagnosis.

Conditions for setting DTC 31:

1. Oxygen sensor-1 present (switching type)

2. And engine run-time greater than 30 seconds.

3. And oxygen sensor voltage does not exceed 0.5V

4. Or oxygen sensor voltage higher than 2.0V

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32OX2 (Oxygen Sensor 2) Fault in Wire Connection.

Fault in Sensor.

Refer to GM Service Manual for MAF Diagnosis.

Conditions for setting DTC 32:

1. Oxygen sensor-2 present (switching type)

2. And engine run-time greater than 30 seconds

3. And oxygen sensor voltage does not exceed 0.5V

4. Or oxygen sensor voltage higher than 2.0V

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34 Auxiliary Injector(s). Fault in Wire Connection.

Check Pin Location on 31-way connector (A2 and A6).

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Please follow this diagnosis process thoroughly and complete each step. If the condition exhibited is resolved without completing every step, the remaining steps do not need to be performed. If these steps do not resolve the condition, please contact GM TAC for further diagnostic assistance. This diagnostic approach was developed for the vehicle with the VIN you entered and should not be automatically be used for other vehicles with similar symptoms.

Models:

(03, 04 Pontiac Vibe)

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