STEP 1. Connector check: C-310 steering wheel sensor connector
STEP 2. Resistance measurement at C-310 steering wheel sensor connector.
(1) Disconnect C-310 steering wheel sensor connector and measure the resistance available at the wiring harness side of the connector.
(2) Check for continuity between C-310 steering wheel sensor connector terminal No.5 and body ground.OK: Continuity exists (2 Ω or less)
Is the check result normal?
Go to Step 4. Go to Step 3.
STEP 3. Check the wiring harness between C-310 steering wheel sensor connector terminal No.5 and the body ground.
STEP 4. Connector check: C-408 ETACS-ECU connector, C-417 ETACS-ECU connector
STEP 5. Voltage measurement at C-408 ETACS-ECU connector
(1) Disconnect C-306 ETACS-ECU connector and measure the voltage available at the wiring harness side of the connector.
(2) Measure the voltage between C-408 ETACS-ECU connector terminal No.1 and body ground.OK: Approximately system voltage
Is the check result normal?
Go to Step 7. Go to Step 6.
STEP 6. Check the wiring harness between fusible link No. 34 and C-408 ETACS-ECU connector terminal No.1.
STEP 7. Measure the voltage at the C-310 steering wheel sensor connector.
(1) Disconnect C-310 steering wheel sensor connector and measure the voltage at the wiring harness side of the connector.
(2) Turn the ignition switch to the ON position.
(3) Measure the voltage between the terminal No.2 and the body ground.OK: Approximately system voltage
Is the check result normal?
Go to Step 10. Go to Step 8.
STEP 8. Check the fuse No.12.
STEP 9. Check the wiring harness between C-310 steering wheel sensor connector terminal No.2 and C-417 ETACS-ECU connector terminal No.5.
STEP 10. Using scan tool MB991958, check the ETACS system data list
Check the input signal of IG1 relay.- Turn the ignition switch to the ON position.
| Item No. | Item name | Normal condition | Item 254 | IG voltage | Battery positive voltage |
|
OK: Normal condition is displayed.
Is the check result normal?
Replace the steering wheel sensor. Refer to GROUP 54A - ETACS - Input Signal Procedures/Input Signal Procedure 2 "ETACS-ECU does not receive any signal from the ignition switch (IG1)" .