PRE-COLLISION: PRE-COLLISION SYSTEM: U041881; Invalid Data Received from Brake System Control Module Invalid Serial Data Received; 2022 - 2025 MY RAV4 RAV4 HV [12/2021

Last Modified: 05-08-2025	6.11:8.1.0	Doc ID: RM1000000021JCX
Model Year Start: 2022	Model: RAV4	Prod Date Range: [12/2021 - ]
Title: PRE-COLLISION: PRE-COLLISION SYSTEM: U041881; Invalid Data Received from Brake System Control Module Invalid Serial Data Received; 2022 - 2025 MY RAV4 RAV4 HV [12/2021 - ]

DTC

U041881

Invalid Data Received from Brake System Control Module Invalid Serial Data Received

DESCRIPTION

for HV Model:

The millimeter wave radar sensor assembly receives signals related to the brake control condition from the brake actuator assembly (No. 2 skid control ECU) via the CAN communication line.
If the millimeter wave radar sensor assembly receives signals from the brake actuator assembly (No. 2 skid control ECU) indicating a brake control system malfunction, the millimeter wave radar sensor assembly stores DTC U041881.

for Gasoline Model:

The millimeter wave radar sensor assembly receives signals related to the brake control condition from the brake actuator assembly (skid control ECU) via the CAN communication line.
If the millimeter wave radar sensor assembly receives signals from the brake actuator assembly (skid control ECU) indicating a brake control system malfunction, the millimeter wave radar sensor assembly stores DTC U041881.

DTC No.	Detection Item	DTC Detection Condition	Trouble Area
U041881	Invalid Data Received from Brake System Control Module Invalid Serial Data Received	for HV Model: When the ignition switch is ON for 3 seconds or more, the millimeter wave radar sensor assembly receives a brake control system malfunction signal from the brake actuator assembly (No. 2 skid control ECU) for 1 second or more. for Gasoline Model: When the ignition switch is ON for 3 seconds or more, the millimeter wave radar sensor assembly receives a brake control system malfunction signal from the brake actuator assembly (skid control ECU) for 1 second or more.	for HV Model: Millimeter Wave Radar Sensor Assembly Brake actuator assembly (No. 2 skid control ECU) for Gasoline Model: Millimeter Wave Radar Sensor Assembly Brake actuator assembly (Skid control ECU)

CAUTION / NOTICE / HINT

NOTICE:

When replacing the millimeter wave radar sensor assembly, always replace it with a new one. If a millimeter wave radar sensor assembly which was installed to another vehicle is used, the information stored in the millimeter wave radar sensor assembly will not match the information from the vehicle and a DTC may be stored.
When the millimeter wave radar sensor assembly has been replaced with a new one, it is necessary to perform millimeter wave radar sensor assembly beam axis alignment and to clear the vehicle control history. Before performing the Driving Adjustment, make sure to read Before Starting Driving Adjustment.
HINT:

Beam axis alignment of the millimeter wave radar sensor assembly can be performed using either Triangle Target, Flat Surface Target or Driving Adjustment.

Triangle Target: Click here

Flat Surface Target: Click here

Driving Adjustment: Click here

PROCEDURE

1.	CHECK ELECTRONICALLY CONTROLLED BRAKE SYSTEM

(a) Check for DTCs.

for HV Model:

Click here

for Gasoline Model:

Click here

Chassis > Brake/EPB > Trouble Codes

OK:

Electronically controlled brake system DTCs are not output.

HINT:

If U041881 is output in the pre-collision system, electronically controlled brake system DTCs may also have been output. Check the electronically controlled brake system first.

REPLACE MILLIMETER WAVE RADAR SENSOR ASSEMBLY

GO TO ELECTRONICALLY CONTROLLED BRAKE SYSTEM

for HV Model:

Click here

for Gasoline Model:

Click here