Keyless Entry System - Remote: Wiring Lexus RX I

Harness Connector Disconnected

Disconnect wireless door lock ECU harness connector. Using DVOM, ensure continuity is constant between ground and terminal No. 1 (White/Black wire) of harness connector. (Scheme 4) If circuit value is not as specified, inspect circuit and related components. See WIRING DIAGRAMS. Repair as necessary.

Harness Connector Connected

1. Connect wireless door lock ECU harness connector. Remove key from ignition switch. Using DVOM, measure voltage (backprobe) between ground and terminal No. 3 of harness connector. (Scheme 4) Ensure voltage is less than one volt intermittently. If voltage is not as specified, inspect circuit and related components. See «WIRING DIAGRAMS»(ref-3419-S22085945902000050300000). If voltage is as specified, go to next step.
2. Using DVOM, measure voltage (backprobe) between ground and terminal No. 4 of harness connector. (Scheme 4) Ensure voltage is 4.5-5.5 volts with remote transmitter off, and less than one volt with remote transmitter operating. If voltage is not as specified, inspect circuit and related components. See «WIRING DIAGRAMS»(ref-3419-S22085945902000050300000). If voltage is as specified, go to next step.
3. Using DVOM, measure voltage (backprobe) between ground and terminal No. 5 of harness connector. (Scheme 4) Ensure voltage is 4.5-5.5 volts with remote transmitter off, and less than one volt with remote transmitter operating. If voltage is as specified, wireless door lock ECU is faulty. If voltage is not as specified, inspect circuit and related components. See «WIRING DIAGRAMS»(ref-3419-S22085945902000050300000).

Scheme 4