Code No.U1006 Security alarm siren LIN timeout <Vehicles with security alarm sensor>



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


JUDGEMENT CRITERIA


The ETACS-ECU will set diagnosis code No. U1006 when no signals are received from the security alarm siren.

PROBABLE CAUSES




DIAGNOSIS PROCEDURE


STEP 1. Resistance measurement at the security alarm siren connector


(1)Disconnect the connector, and measure at the wiring harness side.
(2)Measure the resistance between the security alarm siren 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 security alarm siren connector (earth terminal) and the 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 security alarm siren connector.


(1)Disconnect the connector, and measure at the wiring harness side.
(2)Measure the voltage between the security alarm siren connector (LITI 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, short to earth, and open circuit in LITI line between ETACS-ECU connector and security alarm siren 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 BUP4 line between ETACS-ECU connector and security alarm siren connector.


Q. Is the check result normal?

Go to Step 6.
Repair the connector(s) or wiring harness.

STEP 6. Replace the security alarm siren temporarily, and check whether the diagnosis code is set.


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

Q. Is the diagnosis code set?

Replace the security alarm siren.
A poor connection, open circuit, or other intermittent malfunctions in the LIN bus lines between the security alarm sensor and the ETACS-ECU (Refer to GROUP 00 - How to Cope with Intermittent Malfunction ).