Test No. 1: Tachometer, Fuel & Engine Coolant Temperature Gauges Do Not Operate

Check ECU-ACC (5-amp), ECU-B (7.5-amp), ECU-IG No. 2 (10-amp), GAUGE No. 1 (10-amp), PANEL (5-amp), and RADIO (15-amp) fuses in driver side junction block located under left side of instrument panel. See Figure. If fuses are okay, go to next step. If fuses are defective, repair short in wiring connected to identified fuse. See INSTRUMENT CLUSTER in SYSTEM WIRING DIAGRAMS article. After repairs have been made, perform confirmation test. See CONFIRMATION TEST .
Check instrument cluster ground circuit. Ground circuit is through Brown wire at 22-pin electrical harness connector C9 terminal A20. See INSTRUMENT CLUSTER in SYSTEM WIRING DIAGRAMS article. If ground circuit is faulty, repair and retest system. If ground circuit is okay, substitute original instrument cluster with a known-good unit and recheck system operation. If system operates properly, original instrument cluster was defective. If system still does not operate properly, perform instrument cluster pin voltage check. See INSTRUMENT CLUSTER under PIN VOLTAGE TESTS. Check wiring harness and electrical connectors for an intermittent problem. Repair wiring harnesses or connectors as necessary. If voltage values, harnesses and connectors are okay, replace instrument cluster. After repairs have been made, perform confirmation test. See CONFIRMATION TEST .

Fig 1: Identifying Instrument Cluster & Multi-Display Information Center Electrical Harness Connectors & Terminals