Inspection Procedure 17: Variable Geometry Solenoid Valve System
OPERATION
- Power is supplied to the variable geometry solenoid valve (terminal No. 5)
from the engine control relay (terminal No. 2).
- The engine-ECU (terminal No. 44) makes the power transistor in the unit be in "ON"
position, and that makes currents go on the variable geometry solenoid valve (terminal No. 4).
FUNCTION
- In response to a signal from the engine-ECU, the variable geometry solenoid
valve controls the boost pressure.
PROBABLE CAUSES
- Failed variable geometry solenoid valve
- Open/short circuit or harness damage in variable geometry solenoid valve circuit
or loose connector contact
- Failed engine-ECU
DIAGNOSIS PROCEDURE |
STEP 1. Connector check: A-56 emission control solenoid assembly connector |
Q.
Is the check result normal?
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Go to Step 2 . |
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Repair or replace the connector. |
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STEP 2. Perform voltage measurement at A-56 emission control solenoid assembly connector. |
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OK: System voltage |
Q.
Is the check result normal?
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Go to Step 4 . |
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Go to Step 3 . |
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STEP 3. Connector check: A-33X engine control relay connector |
Q.
Is the check result normal?
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|
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Repair or replace the connector. |
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STEP 4. Perform voltage measurement at B-05 engine-ECU connector. |
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OK: System voltage |
Q.
Is the check result normal?
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Go to Step 8 . |
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Go to Step 5 . |
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STEP 5. Connector check: B-05 engine-ECU connector |
Q.
Is the check result normal?
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Go to Step 6 . |
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Repair or replace the connector. |
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STEP 6. Check harness between A-56 (terminal No. 4) emission control solenoid assembly connector and B-05 (terminal No. 44) engine-ECU connector. |
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Q.
Is the check result normal?
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Go to Step 7 . |
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Repair the damaged harness wire. |
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STEP 7. Check the trouble symptoms. |
Q.
Does trouble symptom persist?
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Replace the emission control solenoid assembly. |
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Intermittent malfunction (Refer to GROUP 00 - How to Use Troubleshooting/Inspection
Service Points - How to Cope with Intermittent Malfunctions ). |
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STEP 8. Connector check: B-05 engine-ECU connector |
Q.
Is the check result normal?
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Go to Step 9 . |
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Repair or replace the connector. |
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STEP 9. Check harness between A-56 (terminal No. 4) emission control solenoid assembly connector and B-05 (terminal No. 44) engine-ECU connector. |
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Q.
Is the check result normal?
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Go to Step 10 . |
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Repair the damaged harness wire. |
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STEP 10. Check harness between A-56 (terminal No. 5) emission control solenoid assembly connector and A-33X (terminal No. 2) engine control relay connector. |
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Q.
Is the check result normal?
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Go to Step 11 . |
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Repair the damaged harness wire. |
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STEP 11. Replace the emission control solenoid assembly. |
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Q.
Does trouble symptom persist?
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Replace the engine-ECU. |
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The check is end. |
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