ECM Harness Handling

Securely connect ECM harness connectors.
A poor connection can cause an extremely high (surge) voltage to develop in coil and condenser, thus resulting in damage to ICs.
Keep ECM harness at least 10 cm (3.9 in.) away from adjacent harnesses to prevent an engine control system malfunction due to receiving external noise, degraded operation of ICs, etc.
Keep engine control system parts and harnesses dry.
Before removing parts, turn off ignition switch and then disconnect battery ground cable.