Code No. U1005: Clearance Warning Control Unit Time-out

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

DIAGNOSIS PROCEDURE

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

Using M.U.T.-III, perform CAN bus line diagnosis.

Q. Is the check result normal?

	Go to Step 2.

	Correct CAN bus line (Refer to GROUP 54C - Troubleshooting - CAN Bus Diagnostics Table ), and then go to Step 6.

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

Confirm whether the diagnosis codes are set in the clearance warning control unit.

Q. Is the diagnosis code set?

	Perform the troubleshooting of clearance warning control unit (Refer to GROUP 54A - Unintended Acceleration mitigation System/BSW/Corner Sensor System, Clearance Warning Control Unit, Troubleshooting ).

	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 the diagnosis code set?

	Go to Step 4.

	Go to Step 5.

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

Reconfirm whether the diagnosis codes are set in the engine-ECU.

Erase the diagnosis codes being set.
Ignition switch: "LOCK" (OFF) → "ON"
Confirm whether the diagnosis codes are set.

Q. Is the diagnosis code set?

	After replacing the 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

Reconfirm whether the diagnosis codes are set in the engine-ECU.

Erase the diagnosis codes being set.
Ignition switch: "LOCK" (OFF) → "ON"
Confirm whether the diagnosis codes are set.

Q. Is the diagnosis code set?

	Replace the engine-ECU, and then 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

Reconfirm whether the diagnosis codes are set in the engine-ECU.

Erase the diagnosis codes being set.
Ignition switch: "LOCK" (OFF) → "ON"
Confirm whether the diagnosis codes are set.

Q. Is the diagnosis code set?

	Go to Step 1.

	The check is end.