DTC 42 - Auto Shutdown Relay Control Circuit - Test FC-12A

1. Using DRB-II, erase fault codes and actuate ASD relay. ASD relay only supplies battery voltage to alternator field. If relay is not clicking, go to step 3). If relay is clicking, condition required to set fault is not present at this time. AUTO SHUTDOWN RELAY CONTROL CIRCUIT fault sets if ASD and fuel pump relay control circuit is not in its proper state when monitored by PCM during cranking. Possible causes are open or short in ASD and fuel pump relay control circuit, open or short in control circuit wire, open or shorted ignition power feed to relays, and failed control circuit driver in PCM.
2. Inspect wiring and connectors. Repair harness or connector as necessary. Perform TEST VER-1. If no problems were found with wiring and connectors, wiggle harness between PCM and relay. Ensure actuator test is still running. Using DRB-II, read faults. If AUTO SHUTDOWN RELAY CONTROL CIRCUIT fault resets, repair harness or connector where problem occurred. Perform TEST VER-1. If fault did not reset, see INACTIVE FAULT CONDITION. Test is complete. Perform TEST VER-1.
3. Remove ASD relay. substitute another relay. If substitute relay clicks, replace original ASD relay. Perform TEST VER-1. If substitute relay does not click, remove substitute relay. Using DRB-II in voltmeter mode, probe ASD relay connector terminal "A", 12-volt ignition feed circuit (Dark Blue wire). If reading is 10 volts or less, repair open Dark Blue wire. Perform TEST VER-1. If reading is more than 10 volts, disconnect PCM.
4. Using DRB-II in ohmmeter mode, probe ASD relay connector terminal "C", control circuit (Dark Blue/Yellow wire). If resistance is less than 5 ohms, repair wire for a short to ground. Perform TEST VER-1. If reading is 5 ohms or more, check resistance of ASD relay connector control circuit (Dark Blue/Yellow wire) between PCM terminal No. 51 and ASD relay terminal "C" using an external ohmmeter. If resistance is 5 ohms or more, repair open Dark Blue/Yellow wire. Perform TEST VER-1. If resistance is less than 5 ohms, replace PCM. Perform TEST VER-1.