Test J: Powertrain Control Module (Pcm) Does Not Respond To NGS Tester
NOTE:
If test results indicate PCM is faulty, always check for any engine performance related Diagnostic Trouble Codes (DTCs) prior to replacing PCM. If any DTCs are present, service DTCs as necessary and retest. See appropriate TESTS W/CODES
article in the ENGINE PERFORMANCE section.
- Turn ignition off. Disconnect PCM connector located in right rear of engine compartment. See Figure. Inspect connector for loose, damaged or corroded terminals. Repair connector as necessary and retest system for normal operation. If connector is okay, reconnect connector. Turn ignition on. Perform data link diagnostic procedure. See DATA LINK DIAGNOSTIC TEST under COMMUNICATION NETWORK DIAGNOSTICS. If NGS tester does not indicate PCM: NO RESPONSE ON CKT 914 (BUS +), go to step 6). If NGS tester indicates PCM: NO RESPONSE ON CKT 914 (BUS +), go to next step.
- Turn ignition off. Disconnect NGS tester. Disconnect PCM connector. Using an ohmmeter, measure resistance of Tan/Orange wire between terminal No. 16 at PCM connector and terminal No. 2 at Data Link Connector (DLC). See Figure and Fig 1. If resistance is less than 5 ohms, replace PCM and retest system for normal operation. If resistance is 5 ohms or more, go to next step.
- Disconnect 84-pin connector C217 located behind left side of instrument panel. See Figure. Inspect connector for loose, damaged or corroded terminals. Repair connector as necessary and retest system for normal operation. If connector is okay, measure resistance of Tan/Orange wire between terminal No. 55 at connector C217 and terminal No. 2 at DLC. See Figure and Figure. If resistance is less than 5 ohms, go to next step. If resistance is 5 ohms or more, repair open in Tan/Orange wire between connector C217 and DLC. Retest system for normal operation.
- Disconnect Black 40-pin connector C139 located in left rear of engine compartment. See Figure. Inspect connector for loose, damaged or corroded terminals. Repair connector as necessary and retest system for normal operation. If connector is okay, measure resistance of Tan/Orange wire between terminal No. 55 at connector C217 and terminal No. 19 at connector C139. See Figure and Fig 1. If resistance is less than 5 ohms, go to next step. If resistance is 5 ohms or more, repair open in Tan/Orange wire between connector C217 and connector C139. Retest system for normal operation.
- Disconnect 16-pin connector C127 located in left rear of engine compartment. See Figure. Inspect connector for loose, damaged or corroded terminals. Repair connector as necessary and retest system for normal operation. If connector is okay, measure resistance of Tan/Orange wire between terminal No. 16 at PCM connector and terminal No. 2 at connector C127. See Fig 1 and Fig 2. If resistance is less than 5 ohms, repair open in Tan/Orange wire between connector C127 and connector C139. Retest system for normal operation. If resistance is 5 ohms or more, repair open in Tan/Orange wire between PCM and connector C127. Retest system for normal operation.
- Turn ignition off. Disconnect NGS tester. Measure resistance of Pink/Light Blue wire between terminal No. 15 at PCM connector and terminal No. 10 at DLC. See Figure and Fig 1. If resistance is less than 5 ohms, replace PCM and retest system for normal operation. If resistance is 5 ohms or more, go to next step.
- Disconnect 84-pin connector C217 located behind left side of instrument panel. See Figure. Inspect connector for loose, damaged or corroded terminals. Repair connector as necessary and retest system for normal operation. If connector is okay, measure resistance of Pink/Light Blue wire between terminal No. 79 at connector C217 and terminal No. 10 at DLC. See Figure and Figure. If resistance is less than 5 ohms, go to next step. If resistance is 5 ohms or more, repair open in Pink/Light Blue wire between connector C217 and DLC. Retest system for normal operation.
- Disconnect 40-pin connector C139 located in left rear of engine compartment. See Figure. Inspect connector for loose, damaged or corroded terminals. Repair connector as necessary and retest system for normal operation. If connector is okay, measure resistance of Pink/Light Blue wire between terminal No. 23 at connector C139 and terminal No. 79 at female half of connector C217. See Figure and Figure. If resistance is less than 5 ohms, go to next step. If resistance is 5 ohms or more, repair open in Pink/Light Blue wire between connector C139 and connector C217. Retest system for normal operation.
- Disconnect 16-pin connector C127 located in left rear of engine compartment. See Figure. Inspect connector for loose, damaged or corroded terminals. Repair connector as necessary and retest system for normal operation. If connector is okay, measure resistance of Pink/Light Blue wire between terminal No. 15 at PCM connector and terminal No. 3 at connector C127. See Fig 1 and Fig 2. If resistance is less than 5 ohms, repair open in Pink/Light Blue wire between connector C127 and connector C139. Retest system for normal operation. If resistance is 5 ohms or more, repair open in Pink/Light Blue wire between PCM and connector C127. Retest system for normal operation.