Before replacing the ECU, ensure
that the communication circuit is normal.
JUDGEMENT CRITERIA
The ETACS-ECU will set diagnosis code No. U0169 when no signals are received from the
sunroof control unit.
PROBABLE CAUSES
Faulty sunroof control unit
Malfunction of the LIN bus
DIAGNOSIS PROCEDURE
STEP 1. Connector check: C-316 ETACS-ECU connector, D-04
sunroof control unit connector
Q.
Is the check result normal?
Go to Step 2.
Repair the defective connector.
STEP 2. Check the wiring harness wires between C-316 ETACS-ECU connector
terminal No. 1 and D-04 sunroof control unit connector terminal No. 7.
Check the communication lines for open circuit.
Q.
Is the check result normal?
Go to Step 3.
Repair the wiring harness.
STEP 3. 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 the LOCK (OFF) position to the ON position.
(3)Check if diagnosis code is set.
Q.
Is the diagnosis code set?
Replace the sunroof control unit.
A poor connection, open circuit, or other intermittent malfunctions in the LIN
bus lines between the sunroof control unit and the ETACS-ECU (Refer to GROUP 00 - How
to Cope with Intermittent Malfunction ).
)
)
)
)
Go to Step 2.
Repair the defective connector.
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