caution | Before replacing the ECU,
ensure that the power supply circuit, the earth circuit and the communication circuit are normal. |
DIAGNOSIS PROCEDURE |
STEP 1. Check the combination meter. |
Check whether the combination meter works normally. |
Q.
Is the check result normal?
|
Go to Step 2. |
|
Diagnose the combination meter (Refer to Combination Meter -
Troubleshooting ). |
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STEP 2. Connector check: C-206 steering wheel voice-control switch connector |
Q.
Is the check result normal?
|
Go to Step 3. |
|
Repair the defective connector. |
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STEP 3. Check the wiring harness between C-206 steering wheel voice-control switch connector terminal No.1 and body earth. |
|
Q.
Is the check result normal?
|
Go to Step 4. |
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Repair the wiring harness. |
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STEP 4. Connector check: C-202 and C-204 clock spring connectors |
Q.
Is the check result normal?
|
Go to Step 5. |
|
Repair the defective connector. |
|
STEP 5. Check the clock spring. |
Check whether the clock spring is in good condition (Refer to GROUP 52B -
Air
bag module and clock spring ). |
Q.
Is the check result normal?
|
Go to Step 6. |
|
Replace the clock spring. |
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STEP 6. Check the wiring harness between C-206 steering wheel voice-control switch connector terminal No.4 and C-202 clock spring connector terminal No.1. |
|
Q.
Is the check result normal?
|
Go to Step 7. |
|
Repair the wiring harness. |
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STEP 7. Connector check: C-03 combination meter connector |
Q.
Is the check result normal?
|
Go to Step 8. |
|
Repair the defective connector. |
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STEP 8. Check the wiring harness between C-03 combination meter connector terminal No.23 and C-204 clock spring connector terminal No.6. |
|
Q.
Is the check result normal?
|
|
|
Repair the wiring harness. |
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STEP 9. Retest the system |
Check whether the illumination of the steering wheel voice-control switch comes on normally. |
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 ). |
|
Replace the steering wheel voice-control switch. |
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