Test No. 30: Malfunction Indicator Light (Mil) Does Not Light Up

WARNING: This page is about a different car, the 2002 Toyota Avalon. However, it is still accessible from the selected car via links, so may be relevant.

NOTE: The Malfunction Indicator Light (MIL) is commonly called a "CHECK ENGINE" light and is displayed as graphic icon of an engine on the multi-display information center. The Engine Control Module (ECM) monitors the operating condition and performance of the engine and its related systems and components. The ECM turns the MIL on to signal vehicle operator that a problem has been detected in the engine control system. Ensure engine control system is operating properly and no diagnostic trouble codes are stored before performing this test. See SELF-DIAGNOSTICS - AVALON article in ENGINE PERFORMANCE.

Turn ignition on and monitor MIL on multi-display information center. When ignition is turned on, MIL should illuminate. MIL should go out when engine is started. If bulb does not illuminate, check bulb. If bulb is okay, go to next step. Replace bulb if defective. After repairs have been made, perform confirmation test. See CONFIRMATION TEST .
Check wiring harness and connectors between instrument cluster and Engine Control Module (ECM). See ENGINE PERFORMANCE and INSTRUMENT CLUSTER in SYSTEM WIRING DIAGRAMS article. If wiring and connectors are okay, go to next step. Repair wiring and connectors as required. After repairs have been made, perform confirmation test. See CONFIRMATION TEST .
Check Engine Control Module (ECM). See SELF-DIAGNOSTICS - AVALON article in ENGINE PERFORMANCE. If ECM is okay, go to next step.
Check ECU-ACC (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 multi-display information center ground circuits. See INSTRUMENT CLUSTER in SYSTEM WIRING DIAGRAMS article. If ground circuits are faulty, repair and retest system. If ground circuits are okay, substitute original multi-display information center with a known-good unit and recheck system operation. If system operates properly, original multi-display information center was defective. If system still does not operate properly, perform multi-display information center electrical harness pin voltage checks. See MULTI-DISPLAY INFORMATION CENTER under PIN VOLTAGE TESTS. Check wiring harnesses and electrical connectors for an intermittent problem. Repair wiring harnesses or connectors as necessary. If voltage values, harnesses and connectors are okay, replace multi-display information center. After repairs have been made, perform confirmation test. See CONFIRMATION TEST .