Code No. U0317: Electric Parking Brake ECU Time-out

caution

If diagnosis code U0317 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 Condition

The diagnosis code setting enabled signal is received from ETACS-ECU.

Judgement Criterion

The signals cannot be received from electric parking brake ECU for 0.5 seconds or more.

FAIL-SAFE AND BACKUP FUNCTION

None

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 electric parking brake ECU, by malfunction in the power supply system of electric parking brake ECU, in electric parking brake ECU 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 electric parking brake ECU and malfunction in the power supply system of electric parking brake ECU. 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).

PROBABLE CAUSES

Failed of the harness and the connector
Failed engine-ECU
Failed electric parking brake 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 4.

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

Confirm whether the diagnosis codes are set in the electric parking brake ECU.

Q. Is the diagnosis code set?

	Perform the troubleshooting of electric parking brake system (Refer to GROUP 36 - Troubleshooting - Diagnosis Code Chart ).

	Go to Step 3.

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

Check that the other ECU performing CAN communication with electric parking brake ECU sets diagnosis code No. U0317 [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) to ON
Confirm whether the diagnosis codes are set.

Q. Is the diagnosis code set?

	Go to Step 5.

	Intermittent malfunction in CAN bus line between engine-ECU and electric parking brake ECU (Refer to GROUP 00 - How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunction).

STEP 5. Replace the electric parking brake ECU.

After replacing the electric parking brake ECU, re-check the diagnosis code set.

Q. Is the diagnosis code set?

	Replace the engine-ECU.

	The check is end.