Lexus NX: Control Module Communication Bus OFF (U0073,U0124,U0129,U0293)

Lexus NX Service Manual / Brake / Parking Brake / Electric Parking Brake System / Control Module Communication Bus OFF (U0073,U0124,U0129,U0293)

DESCRIPTION

The parking brake ECU assembly communicates with the hybrid vehicle control ECU, skid control ECU (brake booster with master cylinder assembly) and deceleration sensor (airbag ECU assembly) via CAN communication.

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

Memory

Note

U0073

Control Module Communication Bus OFF

With the power switch on (IG), the bus is off (communication with other ECUs is not possible)

CAN communication system

Yes

An electric parking brake system malfunction is displayed on the multi-information display.

U0124

Lost Communication With Lateral Acceleration Sensor Module

With the power switch on (IG) and the vehicle being driven at 7 km/h (4.3 mph) or more, the parking brake ECU assembly cannot receive signals from the deceleration sensor (airbag ECU assembly).

  • CAN communication system
  • Deceleration sensor (Airbag ECU assembly)

Yes

An electric parking brake system malfunction is displayed on the multi-information display.

U0129

Lost Communication with Brake System Control Module

With the power switch on (IG), the parking brake ECU assembly cannot receive signals from the skid control ECU (brake booster with master cylinder assembly) for approximately 1 second or 10 seconds (malfunction duration differs depending on the signal).

  • CAN communication system
  • Skid control ECU (Brake booster with master cylinder assembly)

Yes

An electric parking brake system malfunction is displayed on the multi-information display.

U0293

Lost Communication with EV ECU

With the power switch on (IG), the parking brake ECU assembly cannot receive signals from the hybrid vehicle control ECU for approximately 1 second or 10 seconds (malfunction duration differs depending on the signal).

  • CAN communication system
  • Hybrid vehicle control ECU

Yes

An electric parking brake system malfunction is displayed on the multi-information display.

PROCEDURE

1.

GO TO CAN COMMUNICATION SYSTEM

(a) Go to CAN communication system.

Click here

NEXT

END

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