Diagnostic Procedure
WARNING: This page is about a different car, the 2002 Lexus ES 300. However, it is still accessible from the selected car via links, so may be relevant.
- Measure voltage between positive and negative terminal of battery. If voltage is 10-14 volts, go to next step. If voltage is not 10-14 volts, repair battery or charging system as necessary.
- Access instrument cluster and disconnect harness connector C7. See INSTRUMENT CLUSTER under REMOVAL & INSTALLATION. Reconnect negative battery cable. Turn ignition switch to ON position. Measure voltage between ground and instrument cluster connector C70, terminal No. 40 (White wire). See Fig 1. If voltage is 10-14 volts, go to next step. If voltage is not 10-14 volts, repair or replace instrument cluster or wiring harness between instrument cluster and battery.
- Disable air bag system. See DISABLING SYSTEM under DISABLING & ACTIVATING AIR BAG SYSTEM. Access air bag sensor assembly and disconnect harness connectors. See AIR BAG SENSOR ASSEMBLY under REMOVAL & INSTALLATION. Reconnect negative battery cable. Turn ignition switch to ON position. If AIR BAG warning light does not illuminate, repair or replace instrument cluster. If AIR BAG warning light illuminates, replace air bag sensor assembly.