Code No.U1500 Column ECU LIN timeout/Not equip


caution Before replacing the ECU, ensure that the communication circuit is normal.

JUDGEMENT CRITERIA


The ETACS-ECU will set diagnosis code No. U1500 when no signals are received from the column switch (column switch ECU).

PROBABLE CAUSES



DIAGNOSIS PROCEDURE

STEP 1. Resistance measurement at the column switch connector
(1)Disconnect the connector, and measure at the wiring harness side.
(2)Measure the resistance between the column switch connector (earth terminal) and the body earth.
OK: Continuity exists (2 Ω or less)

Q. Is the check result normal?
Go to Step 3.
Go to Step 2.

STEP 2. Check of open circuit in body earth line between column switch connector (earth terminal) and body earth

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 connector(s) or wiring harness.

STEP 3. Voltage measurement at the column switch connector.
(1)Disconnect the connector, and measure at the wiring harness side.
(2)Measure the voltage between the column switch connector (power supply terminal) and the body earth.
OK: System voltage

Q. Is the check result normal?
Go to Step 5.
Go to Step 4.

STEP 4. Check of short to power supply, and open circuit in power supply line between column switch connector and junction block connector.

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 connector(s) or wiring harness.

STEP 5. Check of open circuit in LIN line between ETACS-ECU connector and column switch connector.

Q. Is the check result normal?
Go to Step 6.
Repair the connector(s) or wiring harness.

STEP 6. Check whether the diagnosis code is set again.
Check again if the diagnosis code is set in the ETACS-ECU.
(1)Erase the diagnosis code.
(2)Turn the ignition switch from LOCK (OFF) position to ON position.
(3)Check if diagnosis code is set.

Q. Is the diagnosis code set?
Replace the column switch.
A poor connection, open circuit, or other intermittent malfunctions in the LIN bus lines between the column switch and the ETACS-ECU (Refer to GROUP 00 - How to Cope with Intermittent Malfunction ).