Vehicle Damage Warnings

Precautions In Identifying Diagnostic Trouble Codes (DTCs)
- Do not disconnect the connectors from the Powertrain Control Module (PCM),the battery cables, the PCM ground wire harness, or the 15 amp TAIL DOME Fuse. Such disconnection will erase the PCM DTCs in memory.
- Note any DTC indicated first.
- Intermittent malfunctions - There are cases where the scan tool indicates that a DTC representing a fault, which occurred only temporarily, has gone away. In such a cases, it may occur that good parts are replaced unnecessarily. In order to prevent such an error, be sure to follow instructions given below when using the Diagnostic Tables.
- When a malfunction can be identified, that is, it is not an intermittent fault, check the sensor (actuator), wires and each connection to make sure that they are all in good condition.
- When a fault cannot be identified, but the scan tool indicates a DTC:

- Diagnose the fault by using the appropriate DTC charts. If the sensor (actuator), wires and connections are all in good condition , erase the DTC from the PCM memory. Then conduct a test run and check what DTCs are present when the MIL illuminates. Only when it indicates a DTC again, is the fault present.

Notes on System Circuit Inspection
Most intermittent malfunctions are caused by faulty electrical connections or wiring. Perform a careful check of the suspect circuits for any of the following conditions:

- A poor mating of the connector halves, or the terminals not fully seated into the connector body (backed out).

- Improperly formed or damaged terminals. All the connector terminals in the malfunctioning circuits should be carefully reformed to increase contact tension.

- A poor terminal to wire connection.

- Never connect any tester (voltmeter, ohmmeter, etc.) to the Powertrain Control Module (PCM) when the connectors are disconnected. Attempting to do so may cause damage to the PCM.

- Be sure to use a digital Multimeter whose minimum resistance is more than one megohm per volt. Any other digital Multimeter should not be used because accurate measurements are not obtained. (Use DMM J 39200 or an equivalent.)

When checking voltage at each terminal of the PCM electrical connector, be sure to connect the negative (-) probe to the body ground and use a jumper wire to connect the positive (+) probe to the terminal being tested in the PCM connector. Applying the electrical probes of the digital Multimeter improperly may cause a sensor or the PCM to be shorted and damaged.