Lexus NX: Software Incompatibility with Brake System Control Module Not Programmed (U031851)

Lexus NX Service Manual / Engine & Hybrid System / Cruise Control / Dynamic Radar Cruise Control System / Software Incompatibility with Brake System Control Module Not Programmed (U031851)

DESCRIPTION

If the forward recognition camera cannot verify the vehicle information sent from the skid control ECU (brake booster with master cylinder assembly), the forward recognition camera stores DTC U031851.

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

DTC Output from

U031851

Software Incompatibility with Brake System Control Module Not Programmed

The vehicle information sent from the skid control ECU (brake booster with master cylinder assembly) cannot be verified by the forward recognition camera.

Forward recognition camera

Forward recognition camera

CAUTION / NOTICE / HINT

NOTICE:

  • When replacing the forward recognition camera, replace it with a new one. If a forward recognition camera which was installed to another vehicle is used, the information stored in the forward recognition camera will not match the information from the vehicle and a DTC may be stored.
  • When the forward recognition camera is replaced with a new one or the windshield glass is replaced or removed/installed, make sure to perform beam axis adjustment for the forward recognition camera and clear the vehicle control history for each system.

    HINT:

    Forward recognition camera adjustment can be performed by using either One Time Recognition or Sequential Recognition.

    One Time Recognition: Click here

    Sequential Recognition: Click here

PROCEDURE

1.

REPLACE FORWARD RECOGNITION CAMERA

(a) Replace the forward recognition camera with a new one.

Click here

(b) Perform beam axis adjustment for the forward recognition camera.

HINT:

Forward recognition camera adjustment can be performed by using either One Time Recognition or Sequential Recognition.

One Time Recognition: Click here

Sequential Recognition: Click here

NEXT

2.

CLEAR DTC (Radar Cruise2)

(a) Clear the DTCs.

Click here

Powertrain > Radar Cruise2 > Clear DTCs
NEXT

END (FORWARD RECOGNITION CAMERA WAS DEFECTIVE)

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