Toyota Sienna Quiz
Cruise control

Communication Error from ECM to VSC

In this manual: Cruise control
Introduction — 55Service specifications — 7Maintenance — 7Engine — 264U151e automatic transaxle — 108Transfer — 19Propeller shaft — 8Drive shaft — 14Differential — 16Axle — 18Suspension — 37Tire and wheel — 54Brake control — 141Parking brake — 16Steering Column — 11Power steering — 18Air conditioning — 106Supplemental restraint system — 146Seat belt — 22Theft deterrent — 14Engine immobiliser — 17Cruise control — 65Lighting — 61Wiper and washer — 13Door lock — 42Meter — 28Audio / visual — 94Navigation — 108Park assist / monitoring — 33Horn — 5Garage door opener — 42GR-FE Engine control system — 126Supplemental restraint system — 147Other system — 14Windshield / windowglass — 43Mirror — 23Instrument panel — 6Seat belt — 22Seat — 92Engine hood / door — 104Exterior — 39Interior — 5Sliding roof — 9Multiplex communication — 18Can communication — 23
~1min read

DTC P1631 Communication Error from ECM to VSC

DTC U0100 Lost Communication with ECM/PCM "A"

DESCRIPTION

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

DTC No.

DTC Detection Condition

Trouble Area

P1631

 While the dynamic laser cruise control is either preparing for operation or operating, if the ECM continuously receives a logical error signal from the skid control ECU for a certain amount of time, the ECM records this logical error code
  • Communication circuit
  • ECM
  • ABS & traction actuator (Skid control ECU)

U0100

 While the dynamic laser cruise control is either preparing for operation or operating, if the ECM continuously receives a communication cut off signal from the ABS & traction actuator (skid control ECU) for a certain amount of time, the ECM records this communication cut off code
  • Communication circuit
  • ECM
  • 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 CHECK CAN COMMUNICATION SYSTEM

Refer to HOW TO PROCEED WITH TROUBLESHOOTING

END

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