DTC    P1631    Communication Error from ECM to VSC

DTC    U0100    Lost Communication with ECM/PCM "A"

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DESCRIPTION

The ECM sends signals such as A/T information signals, dynamic radar cruise control operation signals, brake operation demand signals, buzzer operation demand signals and low speed mode signals, etc., to the skid control ECU when the dynamic radar cruise control is in operation. The ECM is the only component that has a function to record and output the DTCs in the dynamic radar cruise control system. Therefore if the skid control ECU detects a communication error from the ECM, it sends the malfunction signal back to the ECM.

DTC No.
DTC Detection Condition
Trouble Area
P1631
While dynamic radar cruise control is either preparing for operation or operating, if ECM continuously receives logical error signal from skid control ECU for certain amount of time, ECM records logical error code
  1. Communication circuit
  2. ECM
  3. ABS & traction actuator (Skid control ECU)
U0100
While dynamic radar cruise control is either preparing for operation or operating, if ECM continuously receives communication cut off signal from ABS & traction actuator (skid control ECU) for certain amount of time, ECM records communication cut off code
  1. Communication circuit
  2. ECM
  3. ABS & traction actuator (Skid control ECU)

INSPECTION PROCEDURE

HINT:
This circuit uses CAN communication. Therefore, if there are any malfunctions in the communication circuit, one or more DTCs in the CAN communication system are output.



1.GO TO CAN COMMUNICATION SYSTEM
    Refer to how to proceed with troubleshooting (Click here).