DTC P1676: Frame-To-Powertrain Torque Down Request Signal Line Malfunction (A/T Models Only)
- Perform PCM reset procedure. See PCM RESET PROCEDURE/CLEARING DIAGNOSTIC TROUBLE CODES under SELF-DIAGNOSTIC SYSTEM. Start engine and wait 10 seconds. If DTC P1676 resets, go to next step. If DTC P1676 does not reset, problem is intermittent. System is okay at this time. Check for poor connection(s) or loose wire(s) between ABS/TCS control unit harness connector and PCM harness connectors.
- Turn ignition switch off. Disconnect PCM 20-pin "E" harness connector and ABS/TCS control unit 16-pin harness connector. ABS/TCS control unit is located to right of battery. Check for continuity between ground and PCM 20-pin "E" harness connector terminal No. 16 (Pink wire). See appropriate wiring diagram under ENGINE PERFORMANCE in WIRING DIAGRAMS. If continuity is not present, go to next step. If continuity is present, repair short in Pink wire between PCM 20-pin "E" harness connector terminal No. 16 and ABS/TCS control unit 16-pin harness connector terminal No. 1.
- Check Pink wire for continuity between ABS/TCS control unit 16-pin harness connector terminal No. 1 and PCM 20-pin "E" harness connector terminal No. 16. If continuity is present, go to next step. If continuity is not present, repair open in Pink wire between PCM 20-pin harness connector terminal No. 16 and ABS/TCS control unit 16-pin harness connector terminal No. 1.
- Reconnect PCM 20-pin "E" harness connector. Connect fused jumper wire between PCM 20-pin "E" harness connector terminal No. 16 (Pink wire) and PCM 31-pin "C" harness connector terminal No. 28 (Yellow/Blue wire). Perform PCM reset procedure. See PCM RESET PROCEDURE/CLEARING DIAGNOSTIC TROUBLE CODES under SELF-DIAGNOSTIC SYSTEM. Start engine and wait 60 seconds. If DTC P1678 sets, substitute known-good ABS/TCS control unit, then recheck. If symptom or indication goes away, replace original ABS/TCS control unit. If DTC P1678 does not set, substitute known-good PCM, then recheck. If symptom or indication goes away, replace original PCM.