Code No.P1790 Back up line system
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OPERATION
DIAGNOSIS CODE SET CONDITION
PROBABLE CAUSES
- Damaged harness wires and connectors
- Malfunction of the A/T-ECU
DIAGNOSIS PROCEDURE |
STEP 1. Measure the voltage at A/T-ECU connector C-12. |
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(1)Measure the voltage between A/T-ECU connector C-12 terminal No.38 and earth. OK: System voltage Q.
Is the check result normal? Go to Step 4. Go to Step 2. |
STEP 2. Connectors check: A-115 intermediate connector, C-12 A/T-ECU connector. |
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Check for the contact with terminals.Q.
Is the check result normal?Go to Step 3.Repair the defective connector. |
STEP 3. Check the harness between A/T-ECU connector C-12 terminal No.38 and fusible link. |
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Check the power supply line for short or open circuit.Q.
Is the check result normal?Go to Step 5.Repair the wiring harness. |
STEP 4. Connector check: C-12 A/T-ECU connector. |
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Check for the contact with terminals.Q.
Is the check result normal?Go to Step 5.Repair the defective connector. |
STEP 5. Replace the A/T-ECU and then recheck the diagnosis code. |
| (1)Replace the A/T-ECU. |
| (2)Test drive the vehicle. |
| (3)Check the diagnosis code. |
Q.
Is the diagnosis code set?
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| Go to Step 1. |
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| The inspection is complete. |
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