DYNAMIC RADAR CRUISE CONTROL SYSTEM(for 1AR-FE), Diagnostic DTC:P1631

DTC Code DTC Name
P1631 Communication Error from ECM to VSC

DESCRIPTION

The ECM sends signals such as dynamic radar cruise control operation signals, brake operation demand signals, and buzzer operation demand signals to the skid control ECU (brake actuator assembly) when the dynamic radar cruise control is operating. Therefore, if the skid control ECU (brake actuator assembly) detects a communication error with the ECM, it sends a malfunction signal back to the ECM.

DTC No. Detection Item DTC Detection Condition Trouble Area
P1631 Communication Error from ECM to VSC While the vehicle speed is 36 km/h (22 mph) or more and the dynamic radar cruise control system is operating, the ECM continuously receives a logic error signal from the skid control ECU (brake actuator assembly) for approximately 1 second or more.

  • CAN communication circuit

  • ECM

  • Skid control ECU (brake actuator assembly)

CAUTION / NOTICE / HINT

Note

First check the CAN communication system by following How to Proceed with Troubleshooting. After checking that there are no malfunctions in the CAN communication system, proceed with troubleshooting.

Click here

PROCEDURE


  1. CHECK CAN COMMUNICATION SYSTEM


    1. Using the GTS, check if the CAN communication system is functioning normally.

      Click here

      Result
      Result Proceed to
      CAN communication system DTCs are not output OK
      CAN communication system DTCs are output NG

    NG

    GO TO CAN COMMUNICATION SYSTEM Click here

    OK

  2. CHECK FOR DTCs (RADAR CRUISE 1)


    1. Clear the DTCs.

      Click here


      Powertrain > Radar Cruise1 > Clear DTCs

    2. Perform the following to make sure that the DTC detection conditions are met.

      Tech Tips

      If the following conditions are not met, the malfunction cannot be detected.


      1. Turn the engine switch on (IG).

      2. Turn the dynamic radar cruise control system on using the cruise control main switch (ON-OFF button).

      3. Drive the vehicle at 36 km/h (22 mph) or more for 1 second or more.

    3. Check for DTCs.

      Click here


      Powertrain > Radar Cruise1 > Trouble Codes
      Result
      Result Proceed to
      DTC P1631 is not output A
      DTC P1631 is output B

    A

    USE SIMULATION METHOD TO CHECK Click here

    B

  3. REPLACE ECM


    1. Replace the ECM.

      Click here

      Result
      Proceed to
      NEXT

    NEXT

  4. CHECK FOR DTCs (RADAR CRUISE 1)


    1. Clear the DTCs.

      Click here


      Powertrain > Radar Cruise1 > Clear DTCs

    2. Perform the following to make sure that the DTC detection conditions are met.

      Tech Tips

      If the following conditions are not met, the malfunction cannot be detected.


      1. Turn the engine switch on (IG).

      2. Turn the dynamic radar cruise control system on using the cruise control main switch (ON-OFF button).

      3. Drive the vehicle at 36 km/h (22 mph) or more for 1 second or more.

    3. Check for DTCs.

      Click here


      Powertrain > Radar Cruise1 > Trouble Codes
      Result
      Result Proceed to
      DTC P1631 is not output A
      DTC P1631 is output B

    A

    END (ECM WAS DEFECTIVE)

    B

    REPLACE BRAKE ACTUATOR ASSEMBLY Click here