Toyota Tundra Service Manual: Communication Error from VSC to ECM (P1630)

Toyota Tundra Service Manual / Engine, Hybrid System / Cruise Control / Dynamic Radar Cruise Control System / Communication Error from VSC to ECM (P1630)

DESCRIPTION

The skid control ECU (brake actuator assembly) sends signals such as cruise control cancel signals and brake demand response signals to the ECM when the dynamic radar cruise control system is operating.

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

P1630

Communication Error from VSC to ECM

While the vehicle speed is 36 km/h (22 mph) or more and the dynamic radar cruise control system is operating, communication data from the skid control ECU (brake actuator assembly) is logically inconsistent for approximately 0.5 seconds or more.
  • CAN communication circuit
  • Skid control ECU (brake actuator assembly)
  • ECM

CAUTION / NOTICE / HINT

NOTICE:

  • Before replacing the ECM, refer to Registration.

    Click here

  • 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

(a) Using the Techstream, check if the CAN communication system is functioning normally.

Click here

Result

Proceed to

CAN communication system DTCs are not output

OK

CAN communication system DTCs are output

NG
NG

GO TO CAN COMMUNICATION SYSTEM

OK

2.

CHECK FOR DTCs (RADAR CRUISE1)

(a) Clear the DTCs.

Click here

(b) Perform the following to make sure that the DTC detection conditions are met.

HINT:

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

  1. Turn the ignition switch to ON.
  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 0.5 seconds or more.

(c) Check for DTCs.

Click here

Result

Proceed to

DTC P1630 is not output

A

DTC P1630 is output

B
A

USE SIMULATION METHOD TO CHECK

B

3.

REPLACE SKID CONTROL ECU (BRAKE ACTUATOR ASSEMBLY)

(a) Replace the skid control ECU (brake actuator assembly).

Click here

NEXT

4.

CHECK FOR DTCs (RADAR CRUISE1)

(a) Clear the DTCs.

Click here

(b) Perform the following to make sure that the DTC detection conditions are met.

HINT:

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

  1. Turn the ignition switch to ON.
  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 0.5 seconds or more.

(c) Check for DTCs.

Click here

Result

Proceed to

DTC P1630 is not output

A

DTC P1630 is output

B
A

END
B

REPLACE ECM

    Brake System (P1578)

    Communication Error from ECM to VSC (P1631)

    See More:

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    DIAGNOSIS SYSTEM 1. SYMPTOM SIMULATION HINT: The most difficult case in troubleshooting is when no problem symptoms occur. In such a case, a thorough problem analysis must be carried out. A simulation of the same or similar conditions and environment in which the problem occurred in the customer' ...

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