Key Hole Illumination Check

Measure voltage by backprobing between Smart Entrance Control Unit (SECU) 18-pin connector terminal No. 1 (Red/Yellow wire) and ground. With ignition key inserted into lock cylinder, battery voltage should be present. Press UNLOCK button on remote controller. Voltage should be zero volts. If voltage is as specified, system is functioning correctly. If voltage is not as specified, inspect Red/Yellow wire for open or short. Repair as needed. If circuit is okay, replace key illumination unit.