STEP 1. M.U.T.-IIISE other system's diagnosis code
STEP 2. Check the heated steering wheel switch.
STEP 3. Check the clock spring.
STEP 4. Check the heated steering wheel relay.
STEP 5. Resistance measurement at the heated steering wheel relay connector (earth terminal).
(1) Disconnect the relay, and measure at the wiring harness side.
(2) Resistance between the heated steering wheel relay connector (terminal No.1) and body earth.OK: Continuity exists (2 Ω or less)
Is the check result normal?
Go to Step 7.
Go to Step 6.
STEP 6. Check of open circuit in earth line between heated steering wheel relay connector (terminal No.1) and body earth.
STEP 7. Check of short to power supply, short to earth, and open circuit in IG1 line between ETACS-ECU and heated steering wheel relay connector.
Is the check result normal?
Go to Step 8.
Repair the connector(s) or wiring harness.
STEP 8. Voltage measurement at the between heated steering wheel relay connector (power supply terminal)
(1) Disconnect the relay, and measure at the wiring harness side.
(2) Measure the voltage between the heated steering wheel relay connector (terminal No.3) and body earth.OK: Approximately system voltage
Is the check result normal?
Go to Step 11.
Go to Step 9.
STEP 9. Check the fusible link and relay box.
Is the check result normal?
Go to Step 10.
Repair the fusible link and relay box.
STEP 10. Check of short to power supply, short to earth, and open circuit in power supply line between fusible link and heated steering wheel relay connector (terminal No.3) connector
STEP 11. Resistance measurement at the C-311 clock spring connector (earth terminal).
(1) Disconnect the connector, and measure at the wiring harness side.
(2) Resistance between the C-311 clock spring connector (terminal No.1) and body earth.OK: Continuity exists (2 Ω or less)
Is the check result normal?
Go to Step 13.
Go to Step 12.
STEP 12. Check of open circuit in earth line between C-311 clock spring connector (terminal No.1) and body earth.
STEP 13. Check of short to power supply, short to earth, and open circuit in power supply line between heated steering wheel relay connector and C-311 clock spring connector (terminal No.3)
Is the check result normal?
Go to Step 14.
Repair the connector(s) or wiring harness.
STEP 14. Check of short to power supply, short to earth, and open circuit in input line between heated steering wheel relay connector and C-311 clock spring connector (terminal No.4)
Is the check result normal?
Go to Step 15.
Repair the connector(s) or wiring harness.
STEP 15. Retest the system