Operation CHARM: Car repair manuals for everyone.

Notes on System Circuit Inspection

NOTE: In order to prevent internal damage to the PCM, the ignition must be OFF when disconnecting or reconnecting the PCM connector.

^ Most intermittent malfunctions are caused by faulty electrical connections or faulty wiring. Perform a careful check of the suspect circuits for any of the following conditions:
- Poor mating of the connector halves.
- Electrical terminals that are not fully seated into the connector body (backed out).
- Improperly formed or damaged terminals. All connector electrical terminals in malfunctioning circuits should be carefully reformed in order to increase contact tension.
- A poor terminal to wire connection.
^ Use the J 39200 Digital Multimeter or a equivalent whose minimum resistance is more than one mega ohm per volt. Other digital multimeters should not be used because accurate measurements may not obtained.
^ When checking the voltage at each terminal of the connector while it is connected to the PCM, be sure to connect the negative probe to the body ground and use a jumper wire to connect the positive probe to the connector terminal being tested. Applying the electrical probes of the digital multimeter improperly may cause a sensor or the PCM to be shorted and damaged.