MDX, 3.2CL & 3.2TL
- Check No. 9 (10-amp on MDX, 7.5-amp on 3.2CL and 3.2TL) fuse in underdash fuse/relay box. Check for continuity between instrument panel gauge assembly 14-pin harness connector terminals No. 9, 10 and ground connector terminal G501 located at lower left center of dash (both Black wires). Repair as necessary. If continuity is present in both wires, go to next step.
- Raise and support front of vehicle. Disconnect 14-pin harness connector from instrument panel gauge assembly. Connect negative probe of DVOM to ground and positive probe to gauge assembly 14-pin harness connector terminal No. 2 (Blue/White wire). Place transaxle in Neutral and turn ignition switch on. While observing voltmeter, slowly rotate one wheel (more than 3 mph) with opposite wheel blocked. If voltage does not pulse between zero and about 5 volts, turn ignition switch off and go to next step. If voltage pulses between zero and about 5 volts or more, replace speedometer or printed circuit board.
- Connect negative probe of DVOM to ground and positive probe to PCM 32-pin harness connector terminal No. 9 (Blue/White wire). See Fig 1
. While observing voltmeter, slowly rotate wheel (more than 3 mph) with opposite wheel blocked. If voltage does not pulse between zero and about 5 volts, turn ignition switch off and go to next step. If voltage pulses between zero and about 5 volts, repair open in Blue/White wire between PCM 32-pin harness connector terminal No. 9, instrument panel gauge assembly unit 14-pin harness connector, cruise control unit 14-pin harness connector terminal No. 12 and driver's multiplex control unit 22-pin harness connector terminal No. 14. See WIRING DIAGRAMS article.
Courtesy of AMERICAN HONDA MOTOR CO., INC.
- Turn ignition switch off. Disconnect PCM 32-pin harness connector. Check for continuity in Blue/White wire between ground and PCM 32-pin harness connector terminal No. 9. If continuity is present, repair short to ground in Blue/White wire between PCM 32-pin harness connector terminal No. 9, instrument panel gauge assembly unit 14-pin harness connector terminal No. 2, cruise control unit 14-pin harness connector terminal No. 12 and driver's multiplex control unit 22-pin harness connector terminal No. 14. See WIRING DIAGRAMS article. If continuity is not present, check for bent, loose or corroded terminals. If all connectors are okay. Cut temporary key from a non-immobilizer key blank and tape donor vehicle key to it backwards in order to deactivate immobilizer system during testing. Substitute known-good PCM, then recheck. If symptom or indication goes away, replace original PCM.