| Subject: | No Start With DTC P1626 Or P1631 |
| 98-07 Chevrolet Full Size Trucks (Classic) |
| 98-06 Chevrolet Full Size Utilities and Vans |
| 98 -07 GMC Full Size Trucks (Classic) |
| 98-06 Cadillac Full Size Trucks/Utilities |
| 98-07 Chevrolet Mid Size Truck/Utilities/Vans |
| 98-07 GMC Mid Size Truck/Utilities/Vans |
| 98-04 Oldsmobile Bravada and |
This PI is being superseded to to update the model years. Please discard PIT4001.
The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.
Condition/Concern:
You may experience a start/stall condition with a code P1626 or P1631 set in the PCM. An extended crank condition may cause a code P1626 or P1631 to set when there is no related theft deterrent codes.
Recommendation/Instructions:
To determine if a crank/no start or start/stall condition is being caused by a passlock theft deterrent concern, perform the following steps:
- Connect the Tech 2 to the vehicle, turn ignition to the on position
- Select the "POWERTRAIN" option
- Select "DATA DISPLAY"
- Select engine data and look for the "VTD FUEL DISABLE" parameter
- Crank the engine, If the "VTD FUEL DISABLE" indicates "ACTIVE", The passlock theft deterrent system is disabling the fuel and you need to follow theft deterrent diagnosis. When the engine is cranked, if the "VTD FUEL DISABLE" indicates "INACTIVE",
The no start condition is NOT being caused by a theft deterrent concern and normal no start diagnostic should be followed..
Please follow this diagnostic or repair 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.
