Code No. U1005: Clearance Warning Control Unit Time-out <Vehicles with corner sensor system>

caution

If diagnosis code U1005 is set in the engine-ECU, surely perform CAN bus line diagnosis.

caution

Replace ECU after certainly confirming that the communication circuits are normal.

TROUBLE JUDGEMENT

Check Conditions

After 2 seconds have passed since the ignition switch was turned to "ON" position.
Battery positive voltage is more than 10 V and is less than 16.5 V.

Judgement Criterion

Unable to receive clearance warning control unit signals through the CAN bus line for 4 seconds.

COMMENT ON TROUBLE SYMPTOM

Current malfunction

The failure is possibly caused by malfunction of the harness and connector in CAN bus line between engine-ECU and clearance warning control unit, by malfunction in the power supply system of clearance warning control unit, in clearance warning control unit itself, in engine-ECU.

Past malfunction

Proceed with troubleshooting focusing on malfunction of the harness and connector in CAN bus line between engine-ECU and clearance warning control unit and malfunction in the power supply system of clearance warning control unit. For diagnosis procedure, refer to how to cope with past malfunctions (Refer to GROUP 00 - How to Use Troubleshooting/Inspection Service Points - How to Treat Past Trouble).

note

In the case of past malfunctions, M.U.T.-III CAN bus line diagnosis cannot detect a malfunction even if there is a malfunction in CAN bus. Therefore, check CAN bus line as in the case of response to intermittent malfunctions (Refer to GROUP 00 - How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunctions). It is possible to narrow down areas with a high possibility of malfunctions from diagnosis codes set in each ECU that performs CAN communication (Refer to GROUP 54C - Explanation about the M.U.T.-III CAN Bus Diagnostics).

FAIL-SAFE AND BACKUP FUNCTION

Torque requested by clearance warning control unit is ignored.

PROBABLE CAUSES

Failed harness and connector
Failed clearance warning control unit
Failed engine-ECU

DIAGNOSIS PROCEDURE

STEP 1. M.U.T.-III CAN bus diagnosis

Use M.U.T.-III to perform CAN bus line diagnosis.

Q. Is the check result normal?

	Go to Step 2.

	Repair CAN bus line (Refer to GROUP 54C - Troubleshooting - CAN Bus Diagnostics Table ). After repairing CAN bus line, go to Step 6.

STEP 2. M.U.T.-III diagnosis code

Confirm whether the diagnosis code is set in the clearance warning control unit.

Q. Is diagnosis code set?

	Perform troubleshooting of clearance warning control unit (Refer to GROUP 54A - Ultrasonic Misacceleration Mitigation System/Corner Sensor System - Diagnosis Code Chart ).

	NO : Go to Step 3.

STEP 3. M.U.T.-III diagnosis code

Check that the other ECU performing CAN communication with clearance warning control unit sets diagnosis code No. U1005 [Refer to GROUP 54C - CAN Communication-related Diagnosis Code Table

Q. Is diagnosis code set?

	Go to Step 4.

	Go to Step 5.

STEP 4. M.U.T.-III diagnosis code

Reconfirmation of diagnosis code.

Confirm again whether the diagnosis code is set in the engine-ECU.

Erase the set diagnosis code.
Ignition switch: LOCK (OFF) → ON
Confirm whether the diagnosis codes is set.

Q. Is diagnosis code set?

	After replacing clearance warning control unit, go to Step 6.

	Intermittent malfunction in CAN bus line between engine-ECU and clearance warning control unit (Refer to GROUP 00 - How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunctions).

STEP 5. M.U.T.-III diagnosis code

Reconfirmation of diagnosis code.

Confirm again whether the diagnosis code is set in the engine-ECU.

Erase the set diagnosis code.
Ignition switch: LOCK (OFF) → ON
Confirm whether the diagnosis code is set.

Q. Is diagnosis code set?

	Replace the engine-ECU, go to Step 6.

	Intermittent malfunction in CAN bus line between engine-ECU and clearance warning control unit (Refer to GROUP 00 - How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunctions).

STEP 6. M.U.T.-III diagnosis code

Reconfirmation of diagnosis code.

Confirm again whether the diagnosis code is set in the engine-ECU.

Erase the set diagnosis code.
Ignition switch: LOCK (OFF) → ON
Confirm whether the diagnosis code is set.

Q. Is diagnosis code set?

	Go to Step 1.

	Check end.