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)
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 the body earth.
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
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 BUP1 line between ETACS-ECU connector and column switch connector.
STEP 5. Check of open circuit in DATA line between ETACS-ECU connector and column switch connector.
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.
Is the diagnosis code set?
Replace the column switch (Refer to GROUP 54A - 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
).