P1645

DTC P1645 GATEWAY ECU MALFUNCTION

CIRCUIT DESCRIPTION

DTC Detection Condition:

The ECM receives the operating condition signal (ON/OFF) of the A/C from the A/C ECU, and it also receives the electrical load information from the gateway ECU.

The ECM uses these information to control the engine (idle up, etc.).

INSPECTION PROCEDURE
Troubleshoot the Multiplex Communication System.

HINT: Read freeze frame data using the hand-held tester or the OBD II scan tool. Freeze frame data records the engine conditions when a malfunction is detected. When troubleshooting, it is useful for determining whether the vehicle was running or stopped, the engine was warmed up or not, the air-fuel ratio was lean or rich, etc. at the time of the malfunction.