Lexus NX: 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). |
| 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). |
| 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). |
| 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.
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