Security MIL On With No DTCs - keywords ECM IPC passlock start theft
| Subject: | Security MIL On With No DTCs |
| Models: | 2001-2005 Chevrolet Silverado |
| 2001-2005 GMC Sierra |
| with 6.6L Engine |
This PI is being updated to add model years. Please discard PIT3636.
The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.
Condition/Concern:
Some 2001-2005 Silverado and Sierra Trucks equipped with the 6.6L Diesel engine may have a security MIL on after replacing the BCM or ECM. The engine will start and run with the security MIL on and no DTCs will be set.
Recommendation/Instructions:
To correct this concern, replace the ECM and SPS program the module, but DO NOT perform any type of Theft Deterrent Relearn. After the new ECM is programmed, it will automatically learn the theft password when started.
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.
