Precautions For On Board Diagnostic System of A/T and Engine

The ECCS control module (ECM) has an on board diagnostic system. It will light up the Malfunction Indicator Lamp (MIL) to warn the driver of a malfunction causing emission deterioration.

CAUTION:
^ Be sure to turn the ignition switch "OFF" and disconnect the negative battery terminal before the repair or inspection work. The open/short circuit of the related switches, sensors, solenoid valves, etc. will cause the MIL to light up.
^ Be sure to connect and lock the connectors securely after the work. The loose (unlocked) connector will cause the MIL to light up due to the open circuit. Be sure to connect the connector without water, grease, dirt, bent terminals, etc. in it.
^ Be sure to route and clamp the harnesses properly after work. The interference of the harness with a bracket, etc. may cause the MIL to light up due to the short circuit.
^ Be sure to erase the unnecessary (already fixed) malfunction information in the A/T control unit or ECM before returning the vehicle.