DYNAMIC RADAR CRUISE CONTROL SYSTEM, Diagnostic DTC:P1631

DTC Code DTC Name
P1631 Communication Error from ECM to VSC

DESCRIPTION

The hybrid vehicle control ECU 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 booster with master cylinder assembly) when the dynamic radar cruise control is operating. Therefore, if the skid control ECU (brake booster with master cylinder assembly) detects a communication error with the hybrid vehicle control ECU, it sends a malfunction signal back to the hybrid vehicle control ECU.

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 hybrid vehicle control ECU continuously receives a logic error signal from the skid control ECU for approximately 1 second or more.

  • CAN communication circuit

  • Hybrid vehicle control ECU

  • Skid control ECU (brake booster with master cylinder 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

  • Before replacing the hybrid vehicle control ECU, refer to Service Bulletin.

PROCEDURE


  1. CHECK FOR DTCs (RADAR CRUISE 1)


    1. Clear the DTCs.

      Click here

    2. Make sure that the DTC detection conditions are met.

      Tech Tips

      If the detection conditions are not met, the system cannot detect the malfunction.


      1. Turn the power 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

      Result
      Result Proceed to
      DTC P1631 is not output A
      DTC P1631 is output B

    A

    USE SIMULATION METHOD TO CHECK Click here

    B

  2. REPLACE HYBRID VEHICLE CONTROL ECU


    1. Replace the hybrid vehicle control ECU with a new one.

      Click here

      Result
      Proceed to
      NEXT

    NEXT

  3. CHECK FOR DTCs (RADAR CRUISE 1)


    1. Clear the DTCs.

      Click here

    2. Make sure that the DTC detection conditions are met.

      Tech Tips

      If the detection conditions are not met, the system cannot detect the malfunction.


      1. Turn the power 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

      Result
      Result Proceed to
      DTC P1631 is not output A
      DTC P1631 is output B

    A

    END (HYBRID VEHICLE CONTROL ECU WAS DEFECTIVE)

    B

    REPLACE BRAKE BOOSTER WITH MASTER CYLINDER ASSEMBLY (SKID CONTROL ECU) for LHD: Click here
    REPLACE BRAKE BOOSTER WITH MASTER CYLINDER ASSEMBLY (SKID CONTROL ECU) for RHD: Click here