Diagnostic Table
- Install a scan tool. Does the scan tool power up? If so, go to next step. If no, see SCAN TOOL DOES NOT POWER UP
in ACCESSORIES & EQUIPMENT.
- Turn ON the ignition, with the engine OFF. Attempt to establish communication with the following control modules: Electronic Brake Control Module (EBCM) and Body Control Module (BCM). Does the scan tool communicate with all control modules? If so, go to next step. If not, see appropriate SCAN TOOL DOES NOT COMMUNICATE WITH CLASS 2 DEVICE
in ACCESSORIES & EQUIPMENT.
- Select the display DTCs function on the scan tool for the following control modules:
- Electronic Brake Control Module (EBCM)
- Body Control Module (BCM)
Does the scan tool display any DTCs? If so, go to next step. If not, go to SYMPTOMS .
- Does the scan tool display any DTCs which begin with a "U"? If so, see SCAN TOOL DOES NOT COMMUNICATE WITH CLASS 2 DEVICE
in ACCESSORIES & EQUIPMENT. If not, go to next step.
- Does the scan tool display DTC B1000? If so, see Diagnostic Trouble Code (DTC) List in appropriate Body, Cab Control System article. If not, go to next step.
- Does the scan tool display DTC P0560, or P0620? If so, see SELF DIAGNOSTIC SYSTEM
. If not, see DTC INDEX
.