Diagnosis And Testing - Electronic Vehicle Information Center: Notes

If the problem with the EVIC is an inaccurate or scrambled display, refer to SELF-DIAGNOSTIC TEST  . If the problem with the EVIC is incorrect Vacuum Fluorescent Display (VFD) dimming levels, use a DRB scan tool and the proper Diagnostic article to test for the correct dimming message inputs being received from the Body Control Module (BCM) over the Programmable Communications Interface (PCI) data bus. If the problem is a no-display condition, use the following procedures. For complete circuit diagrams, refer to Overhead Console  in SYSTEM WIRING DIAGRAMS .

1. Press the C/T button.
2. Check the fused B(+) fuse in the junction block. If OK, go to step  3. If not OK, repair the shorted circuit or component as required and replace the faulty fuse.
3. Check for battery voltage at the fused B(+) fuse in the junction block. If OK, go to step  4. If not OK, repair the open fused B(+) circuit to the fused B(+) fuse in the PDC as required.
4. Check the fused ignition switch output (run/start) fuse in the junction block. If OK, go to step  5. If not OK, repair the shorted circuit or component as required and replace the faulty fuse.
5. Turn the ignition switch to the On position. Check for battery voltage at the fused ignition switch output (run/start) fuse in the junction block. If OK, go to step  6. If not OK, repair the open fused ignition switch output (run/start) circuit to the ignition switch as required.
6. Turn the ignition switch to the Off position. Disconnect and isolate the battery negative cable. Remove the overhead console. Check for continuity between the ground circuit cavity of the roof wire harness connector for the EVIC module and a good ground. There should be continuity. If OK, go to step  7. If not OK, repair the open ground circuit to ground as required.
7. Connect the battery negative cable. Check for battery voltage at the fused B(+) circuit cavity of the roof wire harness connector for the EVIC module. If OK, go to step  8. If not OK, repair the open fused B(+) circuit to the fused B(+) fuse in the junction block as required.
8. Turn the ignition switch to the On position. Check for battery voltage at the fused ignition switch output (run/start) circuit cavity of the roof wire harness connector for the EVIC module. If OK, refer to SELF-DIAGNOSTIC TEST  for further diagnosis of the EVIC module and the PCI data bus. If not OK, repair the open fused ignition switch output (run/start) circuit to the fuse in the junction block as required.