Circuit/System Testing
WARNING: This page does not describe the selected car, but rather 7 other vehicles, including the 2008 GMC Yukon XL, 2008 GMC Yukon, 2008 Chevrolet Tahoe, 2008 Chevrolet Suburban, and 2008 Cadillac Escalade EXT. However, it is still accessible from the selected car via links, so may be relevant.
P0815
- Select the Driver Shift Request parameter.
- Disconnect the automatic transmission DSC shift switch connector.
- If the parameter status changes from Upshift to Invalid, replace the DSC shift switch.
- If the parameter status does not change, replace the BCM.
P0816
- Select the Driver Shift Request parameter.
- Disconnect the DSC shift switch connector.
- If the parameter status changes from Downshift to Invalid, replace the DSC shift switch.
- If the parameter status does not change, replace the BCM.
P0826
- Test the 12 volt reference circuit and the tap up and tap down switch signal circuit for a short to ground.
- If the circuits test OK, test the 12 volt reference circuit and the tap up and tap down signal circuit for an open or short to voltage.
- Test the DSC shift switch for correct resistance value, 8.11-8.39 ohms.
- If the resistance is not within specifications, replace the switch assembly.
- If the resistance is within specifications, replace the BCM.