Test D: Tachometer Inoperative
NOTE:
If PCM is replaced, PCM MUST be programmed. If vehicle is equipped with passive anti-theft system, all ignition keys MUST be programmed into PCM. See Appropriate Computer Relearn Procedures in GENERAL INFORMATION.
- Turn ignition switch to RUN position. If instrument cluster warning indicators and gauges are operating, go to next step. If instrument cluster warning indicators and gauges are not operating, perform TEST A: WARNING LIGHTS & GAUGES INOPERATIVE .
- Turn ignition switch to LOCK position. Disconnect instrument cluster harness connector C808A. Turn ignition switch to RUN position. Using external tachometer, measure RPM between ground and terminal No. 8 (White/Black wire) at instrument cluster harness connector C808A. See Figure . If external tachometer shows engine RPM, go to next step. If external tachometer does not show engine RPM, go to step 6 .
- Disconnect remaining instrument cluster harness connectors. Remove instrument cluster. Measure resistance between terminal No. 13 at instrument cluster connector C808A (component side) and tachometer terminal T1 on printed circuit. See Fig 1 . If resistance is 5 ohms or less, go to next step. If resistance is greater than 5 ohms, replace printed circuit.
- Measure resistance between terminal No. 8 at instrument cluster connector C808A (component side) and tachometer terminal T3 on printed circuit. If resistance is 5 ohms or less, go to next step. If resistance is greater than 5 ohms, replace printed circuit.
- Measure resistance between terminal No. 9 at instrument cluster connector C808A (component side) and tachometer terminal T2 on printed circuit. If resistance is 5 ohms or less, replace tachometer or instrument cluster as necessary. If resistance is greater than 5 ohms, replace printed circuit.
- Disconnect Powertrain Control Module (PCM) harness connector C421. PCM is located at right rear of engine compartment. Install EEC-V 104-Pin Breakout Box (014-00950) following manufacturer's instructions to PCM harness connector C421. Measure resistance between terminal No. 8 (White/Black wire) at instrument cluster harness connector C808A and terminal No. 48 at breakout box. See Figure . If resistance is 5 ohms or less, go to next step. If resistance is greater than 5 ohms, repair open in White/Black wire.
- Measure resistance between terminals No. 48 and 24 at breakout box. If resistance is greater than 10 k/ohms, go to next step. If resistance is 10 k/ohms or less, repair short to ground in White/Black wire.
- Turn ignition switch to RUN position. Measure voltage between terminals No. 48 and 97 at breakout box. If voltage is one volt or less, replace PCM. If voltage is greater than one volt, repair short to voltage in White/Black wire.