Diagnosis code No.04 Communication error with sunroof-ECU

caution

If diagnosis code No. 04 is set in the ETACS-ECU, diagnose the CAN bus lines.

Trouble judgment

The ETACS-ECU communicates with the sunroof motor assembly (sunroof-ECU) through the SWS communication line. If there is any trouble in that communication, diagnosis code No. 04 will be set.

note

For vehicles without sunroof, diagnosis code No. 04 does not mean that there is a problem.

COMMENTS ON TROUBLE SYMPTOM

The sunroof motor assembly (sunroof-ECU), the ETACS-ECU, connector(s), or wiring harness between the two may be defective.

POSSIBLE CAUSES

Malfunction of the sunroof motor assembly (sunroof-ECU)
Malfunction of the ETACS-ECU
Damaged harness wires and connectors

DIAGNOSIS PROCEDURE

Step 1. M.U.T.-III CAN bus diagnostics

Use the M.U.T.-III to diagnose the CAN bus lines.

Q. Is the check result normal?

	Go to Step 2.

	Correct the CAN bus line. (Refer to Group 54F - Diagnosis .)

Step 2. Check whether the diagnosis code is reset.

Check again if the diagnosis code is set.

(1)Erase the diagnosis code.

(2)Ignition switch: LOCK (OFF) position to ON

(3)On completion, check that the diagnosis code is not reset.

Q. Is diagnosis code No.04 set?

	Go to Step 3.

	The trouble can be an intermittent malfunction (Refer to GROUP 00 - How to Cope with Intermittent Malfunction ).

Step 3. Connector check: E-07 sunroof motor assembly connector

Q. Is the check result normal?

Go to Step 4.

Repair the defective connector.

Step 4. Voltage measurement at the E-07 sunroof motor assembly connector.

(1)Disconnect the connector, and measure at the wiring harness side.

(2)Voltage between E-07 sunroof motor assembly connector terminal No.1 and body earth
(3)OK: System voltage

Q. Is the check result normal?

Go to Step 6.

Go to Step 5.

Step 5. Check the wiring harness between E-07 sunroof motor assembly connector terminal No.1 to fusible link (5).

note

Prior to the wiring harness inspection, check intermediate connectors C-124, C-128, and repair if necessary.

Check the power supply line for open circuit.

Q. Is the check result normal?

The trouble can be an intermittent malfunction (Refer to GROUP 00 - How to Cope with Intermittent Malfunction

Repair the wiring harness.

Step 6. Voltage measurement at the E-07 sunroof motor assembly connector.

(1)Disconnect the connector, and measure at the wiring harness side.
(2)Turn the ignition switch to the ON position.

(3)Voltage between E-07 sunroof motor assembly connector terminal No.2 and body earth
OK: System voltage

Q. Is the check result normal?

Go to Step 8.

Go to Step 7.

Step 7. Check the wiring harness between E-07 sunroof motor assembly connector terminal No.2 to ignition switch (IG2).

note

Prior to the wiring harness inspection, check junction block connectors C-202 and C-211, and repair if necessary.

Check the power supply line to the ignition switch (IG2) for open circuit.

Q. Is the check result normal?

The trouble can be an intermittent malfunction (Refer to GROUP 00, How to Cope with Intermittent Malfunction

Repair the wiring harness.

Step 8. Resistance measurement at the E-07 sunroof motor assembly connector.

(1)Disconnect the connector, and measure at the wiring harness side.

(2)Continuity between E-07 sunroof motor assembly connector terminal No.5 and body earth
OK: 2Ω or less

Q. Is the check result normal?

Go to Step 10.

Go to Step 9.

Step 9. Check the wiring harness between E-07 sunroof motor assembly connector terminal No.5 to body earth.

Check the earth wires for open circuit.

Q. Is the check result normal?

The trouble can be an intermittent malfunction (Refer to GROUP 00, How to Cope with Intermittent Malfunction

Repair the wiring harness.

Step 10. Connector check: C-221 ETACS-ECU connector

Q. Is the check result normal?

Go to Step 11.

Repair the defective connector.

Step 11. Check the wiring harness between E-07 sunroof motor assembly connector terminal No.10 to C-221 ETACS-ECU connector terminal No.59.

note

Prior to the wiring harness inspection, check joint connector C-01 and intermediate connector C-128, and repair if necessary.

Check the communication lines for open circuit.

Q. Is the check result normal?

Go to Step 12.

Repair the wiring harness.

Step 12. Check whether the diagnosis code is reset.

Replace the sunroof motor assembly (sunroof-ECU), and then check that the diagnosis code is not reset.

(1)Replace the sunroof motor assembly (sunroof-ECU).

(2)Ignition switch: ON

(3)On completion, check that diagnosis code No.04 is not reset.

Q. Is diagnosis code No.04 set?

	Replace the ETACS-ECU.

	The procedure is complete.