Tachometer Inaccurate
- Check fuse No. 12. See Figure . If fuse is okay, go to next step. If fuse is blown, replace fuse and retest system.
- Check for loose wiring connections in engine compartment and at instrument cluster. If connections are okay, go to next step. If any connections are loose, secure properly and retest system.
- Disconnect negative battery cable. Remove instrument cluster. See INSTRUMENT CLUSTER under REMOVAL & INSTALLATION. Disconnect cluster connectors C1 and C3. Check for 3 ohms resistance or less between ground and cluster connectors C3, pin No. 14 (Black/Yellow wire for circuit No. 398 and Brown wire for circuit No. 564) and C1, pin No. 5 (Tan/Yellow wire). Connect battery negative cable. Turn ignition switch to RUN position. Check for battery voltage at cluster connector C3, pin No. 8 (Red/Yellow wire). Turn ignition switch to OFF position. Disconnect battery. If resistances and voltages are correct, go to next step. If readings are incorrect, tachometer is not at fault. Inspect and repair circuit No. 640 (Red/Yellow wire) or No. 11 (Tan/Yellow wire), depending on failed reading, and retest system.
- Check for loose tachometer connector clips on rear of instrument cluster or damaged instrument cluster printed circuit. If connector clips are okay, replace tachometer and retest system. If clips are faulty, tighten or replace clips. Replace instrument cluster printed circuit and retest system.