Dtc C1437 Lost Communication With Ecm

Brake. Toyota Rav4. Aca30, 33, 38 Gsa33 Zsa30, 35
Brake Control. Toyota Rav4. Aca30, 33, 38 Gsa33 Zsa30, 35

DESCRIPTION

WIRING DIAGRAM

INSPECTION PROCEDURE

CHECK HARNESS AND CONNECTOR (MOMENTARY INTERRUPTION)

RECONFIRM DTC

REPAIR OR REPLACE HARNESS OR CONNECTOR (SKID CONTROL ECU - ECM)

RECONFIRM DTC

DTC C1437 Lost Communication with ECM


DESCRIPTION

The skid control ECU receives signals from the ECM via the CAN communication system.

DTC Code
DTC Detection Condition
Trouble Area
C1437
When the IG1 terminal voltage is 10 V or higher and the vehicle speed is 15 km/h (9 mph) or more, data cannot be sent from the ECM for 2 seconds or more.
  1. Engine control system
  2. CAN communication system (Skid control ECU to ECM)
  3. Brake actuator assembly (Skid control ECU)

WIRING DIAGRAM

Refer to DTCs U0073, U0100, U0123, U0124 and U0126 (RAV4_ACA30 RM000000YUO048X_02.html).

INSPECTION PROCEDURE

NOTICE:
When replacing the brake actuator assembly, perform zero point calibration (RAV4_ACA30 RM000001K1O00SX.html).
1.CHECK HARNESS AND CONNECTOR (MOMENTARY INTERRUPTION)

  1. Using the intelligent tester, check for any momentary interruption in the wire harness and connector corresponding to the DTC (RAV4_ACA30 RM000000XHS04QX.html).

    ABS/VSC/TRC:
    Tester Display
    		Measurement Item/Range
    		Normal Condition
    		Diagnostic Note
    EFI Communication Open
    		EFI communication open detection / ERROR or NORMAL
    		ERROR: Momentary interruption
    NORMAL: Normal
    		-

    OK:
    There are no momentary interruptions.
    HINT:
    Perform the above inspection before removing the sensor and connector.


NG
Go to step 3
OK


2.RECONFIRM DTC

  1. Turn the ignition switch off.

  1. Clear the DTCs (RAV4_ACA30 RM000000ONJ027X.html).

  1. Start the engine.

  1. Drive the vehicle at a speed of 15 km/h (9 mph) or more for 10 seconds or more.

  1. Check that no CAN communication system DTC is output (RAV4_ACA30 RM000001W16002X.html).

  1. Check if the same DTC is output (RAV4_ACA30 RM000000ONJ027X.html).

    Result:
    Result
    		Proceed to
    DTC (C1437) is not output.
    		A
    DTC (C1437) is output.
    		B
    DTC (CAN communication system DTC) is output.
    		C
    HINT:
    Refer to the following pages when the DTC C1437 is output.
    1. for 1AZ-FE: RAV4_ACA30 RM000000PD909YX.html.
    2. for 2AZ-FE: RAV4_ACA30 RM000000PD90A0X.html.
    3. for 2GR-FE: RAV4_ACA30 RM000000PD909ZX.html.
    4. for 3ZR-FAE: RAV4_ACA30 RM000000PD90AZX.html.


B
INSPECT ENGINE CONTROL SYSTEM (HOW TO PROCEED WITH TROUBLESHOOTING)

C
INSPECT CAN COMMUNICATION SYSTEM (RAV4_ACA30 RM000001W16002X.html)
A

CHECK FOR INTERMITTENT PROBLEMS (SYMPTOM SIMULATION) (RAV4_ACA30 RM00000135201PX.html)

3.REPAIR OR REPLACE HARNESS OR CONNECTOR (SKID CONTROL ECU - ECM)

  1. Turn the ignition switch off.

  1. Repair or replace the harness or connector.

  1. Check for any momentary interruption between the skid control ECU and the ECM (RAV4_ACA30 RM000000XHS04QX.html).

  1. Check that there is no momentary interruption.


NEXT


4.RECONFIRM DTC

  1. Turn the ignition switch off.

  1. Clear the DTCs (RAV4_ACA30 RM000000ONJ027X.html).

  1. Start the engine.

  1. Drive the vehicle at a speed of 15 km/h (9 mph) or more for 10 seconds or more.

  1. Check that no CAN communication system DTC is output (RAV4_ACA30 RM000001W16002X.html).

  1. Check if the same DTC is output (RAV4_ACA30 RM000000ONJ027X.html).

    Result:
    Result
    		Proceed to
    DTC (C1437) is not output.
    		A
    DTC (C1437) is output.
    		B
    DTC (CAN communication system DTC) is output.
    		C


B
REPLACE BRAKE ACTUATOR ASSEMBLY (RAV4_ACA30 RM000001XV200PX.html)

C
INSPECT CAN COMMUNICATION SYSTEM (RAV4_ACA30 RM000001W16002X.html)
A

END