P1645
DTC P1645 Gateway ECU MalfunctionDESCRIPTION
DTC Detection Condition:
The ECM receives the operating condition signal (ON/OFF) of 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.).
Troubleshoot the Multiplex Communication System.
HINT: Read freeze frame data using the intelligent tester or the OBD II scan tool. The ECM records vehicle and driving condition information as freeze frame data the moment a DTC is stored. 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.