Class 2 Serial Data Line System Check: Testing
WARNING: This page is about a different car, the 1998 Cadillac Eldorado and 1998 Cadillac DeVille. However, it is still accessible from the selected car via links, so may be relevant.
- Connect scan tool. Turn ignition switch to ON position. Attempt to establish communication with PZM. If communication cannot be established, go to next step. If communication can be established, record any DTCs that may be present. For PZM DTCs, go to appropriate DTC test. For other DTCs, see appropriate section.
- Using scan tool, attempt to establish communication with another system on class 2 serial data line. If communication cannot be established, go to CHART A: SCAN TOOL WILL NOT COMMUNICATE . If communication can be established, check for poor connection at PZM Brown 24-pin connector C1, terminals B1 (Orange wire), A1 (Purple wire), A2 (Purple wire), and A12 (Black wire). See WIRING DIAGRAMS . If circuits are okay, replace PZM. See REMOVAL & INSTALLATION.