TCM On-Board Diagnostic (OBD) System Check
NOTE:
Refer to illustrations for PCM and TCM harness connector terminal identification. See Fig 1 and Fig 2.
- Turn ignition switch to LOCK position. Release OD switch (OFF position). Turn ignition on. Observe OD/OFF indicator. If indicator illuminates for at least 4 seconds, go to next step. If indicator does not illuminate, go to step 5). If indicator remains illuminated, go to step 11).
- Using a fused jumper wire, jumper DLC No. 2, terminal No. 1 (Blue/Green wire on Sidekick 1.8L; Blue/Orange wire on all others) to ground. See Figure. If indicator flashes DTC 12, electrical system is operating normally at this time. Check for mechanical related problems. See appropriate overhaul article for further diagnosis. If indicator flashes any DTC other than DTC 12, go to next step. If indicator does not flash a DTC, go to step 4).
- Turn ignition switch to LOCK position. Retrieve DTCs using desired method. See RETRIEVING TROUBLE CODES . If any DTCs are set, identify DTC and diagnose accordingly. See FLASH CODE/DTC IDENTIFICATION table. If no DTCs are set, check for mechanical related problems. See appropriate overhaul article for further diagnosis.
- Turn ignition switch to LOCK position. Disconnect TCM harness connector. Using a DVOM, measure resistance of (Blue/Green wire on Sidekick 1.8L; Blue/Orange wire on all others) between DLC No. 2, terminal No. 1 and TCM harness connector terminal No. 18. If resistance is less than 2 ohms, inspect TCM for poor harness connection. Repair as necessary. If connection is okay, replace TCM. If resistance is not as specified, repair open in appropriate wire between TCM and DLC No. 2. Repeat step 1).
- Turn ignition switch to LOCK position. Using a test light connected to battery positive, probe TCM harness connector terminal No. 20 (White/Black wire). Turn ignition on. If test light illuminates, go to next step. If test light does not illuminate, go to step 8).
- Turn ignition switch to LOCK position. Remove instrument cluster. See appropriate INSTRUMENT PANEL article in ACCESSORIES/SAFETY EQUIPMENT section.
- INSTRUMENT PANEL - Geo Tracker
- INSTRUMENT PANEL - Suzuki Sidekick & X90
OD/OFF indicator bulb. If bulb is okay, go to next step. If bulb filament is open, replace bulb and repeat step 1).
- Using a DVOM, measure resistance in White/Black wire between TCM harness connector terminal No. 20 and OD/OFF indicator bulb terminal at instrument cluster harness connector. If resistance is less than 2 ohms, repair open in instrument cluster printed circuit and/or open in power circuit to instrument cluster. If resistance is not as specified, repair open in White/Black wire between TCM and OD/OFF indicator bulb. Repeat step 1).
- Using a test light connected to ground, probe TCM harness connector terminal No. 26 (Black/White wire on Sidekick 1.8L; Blue/Black wire on all others). If test light illuminates, go to next step. If test light does not illuminate, repair open in appropriate wire between TCM and main relay. Repeat Step 1).
- Using a test light connected to ground, probe TCM harness connector terminal No. 25 (White wire). If test light illuminates, go to next step. If test light does not illuminate, repair open in White wire between TCM and TAIL DOME fuse (15-amp). Repeat Step 1).
- Using a DVOM, measure resistance between ground and TCM harness connector terminal No. 24 (Black/Blue wire). If resistance is 2 ohms or less, inspect TCM for poor harness connection. Repair as necessary. If connection is okay, replace TCM. If resistance is not as specified, repair open in Black/Blue wire between TCM and ground. Repeat step 1).
- Turn ignition switch to LOCK position. Disconnect TCM harness connector. Using a DVOM, measure resistance between ground and TCM harness connector terminal No. 20 (White/Black wire). If resistance is 2 ohms or less, repair White/Black wire for a short to ground between TCM and instrument cluster. If resistance is not as specified, go to next step.
- Remove console and disconnect OD switch harness connector. Using a DVOM, measure resistance between OD switch terminals while depressing switch. If DVOM display changes from open circuit to less than 2 ohms, go to next step. If DVOM display is not as specified, replace OD switch and repeat step 1).
- Using a DVOM, measure resistance between TCM harness connector terminal No. 17 (Orange/Green wire) and OD switch harness connector terminal No. 2 (Orange/Green wire). If resistance is 2 ohms or less, replace TCM. If resistance is not as specified, repair Orange/Green wire for a short to ground between TCM and OD switch. Repeat step 1).