Electronic Control Unit (Constant Idle Speed System)

Turn ignition off and remove passenger kick panel. Push latch to side and disconnect electrical connector from control unit by pulling connector down from top. Remove screw in end of connector cover and separate connector block from cover.
NOTE: Always check terminals through holes in side of connector. Terminal numbers are stamped on side of connector.
To check ground connections, connect ohmmeter between terminal 11 and ground, then 25 and ground. Resistance should be zero ohms. If not, check ground points on intake manifold.
To check power supply, turn ignition on. Connect voltmeter between terminal 18 and ground. Battery voltage should be registered. If not, check wire for short or open. Turn ignition off.
To check system relay, connect voltmeter between terminal 9 and ground. Using a jumper wire, jumper terminal 21 to ground. Relay should energize and battery voltage should be indicated. If not, check for short or ground. If wiring is okay, replace system relay.