Engine Controls - MIL ON/DTC P0172 Set
TECHNICALBulletin No.: 10-06-04-004B
Date: April 30, 2012
Subject: Intermittent Illumination of Malfunction Indicator Lamp (MIL)/Check Engine Light, DTC P0172 Set (Verify Alcohol Content Information in PCM)
Models:
2010 Chevrolet Malibu
2010 Pontiac G6
Equipped with 2.4L 4 Cylinder Engine (VINs B, 0 - RPOs LE5, LE9)
Please refer to GWM/IVH
Supercede:
This bulletin is being revised to update the models to include the 2010 Pontiac G6. Please discard Corporate Bulletin Number 10-06-04-004A (Section 06 - Engine/Propulsion System).
Condition
Some customers may comment on an intermittent illumination of the malfunction indicator lamp (MIL)/check engine light.
Technicians may find a DTC P0172 set.
Correction
Use the procedure below to determine if the PCM has the incorrect alcohol content information.
1. Verify the actual measured percentage of alcohol content using the J-44175-A tester. Refer to Alcohol in Fuel Diagnosis in SI.
If the actual alcohol is less than 15%, determine the "Fuel Alcohol Content" using the Tech 2(R).
2. Install the Tech 2(R) and build the vehicle as a 2010 and select Powertrain.
3. Build the vehicle with an LE9 engine (even if it has the LE5 engine).
- Select Special Functions.
- Select Fuel System (F2).
- Select Fuel Composition Reset (F1).
- The first parameter is "Fuel Alcohol Content" displayed as a percentage. If the Fuel Alcohol Content percentage is above 25%, this is the probable cause of DTC P0172.
- From this screen the "Fuel Alcohol Content" can be reset to zero by pressing the lower right Tech 2(R) button. It will then display 0% when it's reset. Finally, reprogram the PCM with the latest calibration. This will correct for the PCM alcohol calculations.
Note
The PCM must be reset from this screen. It does not reset to zero when the PCM is reprogrammed.
Warranty Information
For vehicles repaired under warranty, use:
