Code No.U1500: Column-ECU time-out




TROUBLE JUDGEMENT



COMMENT ON TROUBLE SYMPTOM


The M.U.T.-III shows a diagnosis code status as active.
  • Connector(s) or wiring harness in the LIN bus lines between the column-ECU and the ETACS-ECU, the power supply system of the column-ECU, or the column-ECU itself may be defective.
The M.U.T.-III shows a diagnosis code status as stored.
  • If diagnosis code No.U1500 is stored as a past trouble, carry out diagnosis with particular emphasis on wiring and connector(s) in the LIN bus line between the column-ECU and the ETACS-ECU, and the power supply system of the column-ECU. For diagnosis procedures, refer to GROUP 00, How to Use Troubleshooting/Inspection Service Points - How to Treat Past Trouble .

PROBABLE CAUSES



  • Malfunction of the lighting switch
  • Damaged harness wires and connectors

DIAGNOSIS PROCEDURE

STEP 1. Connector check: C-219 ETACS-ECU connector, C-302 column switch connector



Q. Is the check result normal?

Go to Step 2.

Repair the defective connector. Go to Step 7.

STEP 2. Resistance measurement at the C-302 column switch connector


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

(2)Measure the resistance between the C-302 column switch connector terminal No. 4 and the body earth.
OK: Continuity exists (2 Ω or less)

Q. Is the check result normal?

Go to Step 4.

Go to Step 3.

STEP 3. Check the wiring harness between C-302 column switch connector terminal No. 4 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 use Troubleshooting/inspection Service Points - How to Cope with Intermittent Malfunction ).

Repair the wiring harness.

STEP 4. Voltage measurement at the C-302 column switch connector.


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

(2)Measure the voltage between the C-302 column switch connector terminal No. 1 and the body earth.
OK: System voltage

Q. Is the check result normal?

Go to Step 6.

Go to Step 5.

STEP 5. Check the wiring harness between C-302 column switch connector terminal No. 1 and the C-209 junction block connector terminal No. 2



Check the power supply line for open circuit and short circuit.


note Prior to the wiring harness inspection, check joint connector C-132, and repair if necessary.

Q. Is the check result normal?

The trouble can be an intermittent malfunction (Refer to GROUP 00 - How to use Troubleshooting/inspection Service Points - How to Cope with Intermittent Malfunction ).

Repair the wiring harness.

STEP 6. Check the wiring harness between C-219 ETACS-ECU connector terminal No.54 and C-302 column switch connector terminal No.3.



Check the communication line for open circuit.

Q. Is the check result normal?

Go to Step 7.

Repair the wiring harness. Go to Step 7.

STEP 7. Check whether the diagnosis code is reset.
Check again if the diagnosis code is set to the ETACS-ECU.
(1)Erase the diagnosis code.
(2)Turn the ignition switch from "LOCK" (OFF) position to "ON" position.
(3)On completion, check that the diagnosis code is reset.

Q. Is the diagnosis code set?
Replace the lighting switch.
A poor connection, open circuit or other intermittent malfunction is present in the LIN bus lines between the column-ECU and the ETACS-ECU (Refer to GROUP 00, How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunctions ).