PCM and TCM Power Mode Backup Strategy
WARNING: This page is about a different car, the 2006 Chevrolet Corvette. However, it is still accessible from the selected car via links, so may be relevant.
The PCM and TCM remain in the last known power mode state until it can determine its backup system power mode based on their discrete Accessory/Wake up and Run/Crank signal inputs.
PCM and TCM Power Mode Backup Strategy
| Accessory/Wake Up Signal State | Run/Crank Signal State | Power Mode Determined |
|---|---|---|
| Inactive | Inactive | Off |
| Active | Inactive | Accessory |
| Active | Active | Run |
| Inactive | Active | Crank |