ECM Power and Ground Circuit Check: Troubleshooting
NOTE:
- Before performed troubleshooting, be sure to read the PRECAUTIONS OF ECM CIRCUIT INSPECTION .
- When measuring circuit voltage, resistance and/or pulse signal at ECM connector, connect the special tool to ECM and/or the ECM connectors referring to INSPECTION OF ECM AND ITS CIRCUITS .
TROUBLESHOOTING PROCEDURES
| Step | Action | YES | NO |
|---|---|---|---|
| 1 | Circuit fuse check
|
Go to Step 2. | Replace fuse (s) and check for short in circuits connected to fuse(s). |
| 2 | Power supply circuit check
|
Go to Step 3. | "WHT/RED" wire is open circuit. |
| 3 | Ignition signal check (other than Canada model)
|
Go to Step 4. | Canada model: Check for open circuit in "BLK/WHT", "BLK/YEL" and "GRN" wire is open circuit. If wire is OK, ID controller is faulty. Other than Canada model: "BLK/WHT" and/or "GRN" wire is open circuit. |
| 4 | Main relay circuit check
Is voltage 10 - 14 V? |
Go to Step 5. | Go to Step 9. |
| 5 | Main relay circuit check
|
Go to Step 7. | Go to Step 6. |
| 6 | ECM ground circuit check
|
Substitute a known-good ECM and recheck. | "BLK/ORN" or "BLK" wire is open or high resistance circuit. |
| 7 | Main relay circuit check
|
Go to Step 11. | Go to Step 8. |
| 8 | Main relay circuit check
Is resistance 1 Ω or less? |
Go to Step 11. | "BLK/RED" wire is open circuit or high resistance circuit. |
| 9 | Main relay circuit check
|
Go to Step 10. | "BLK/YEL" wire is open circuit. |
| 10 | Main relay check
|
"BRN/WHT" wire is open or high resistance circuit. | Replace main relay. |
| 11 | Sensor 5 V power source circuit check
|
ECM power and ground circuit is in good condition. | Go to Step 12. |
| 12 | Sensor 5 V power source circuit check
|
Check internal short circuit of EVAP leak check module, TP sensor, A/C refrigerant pressure sensor and/or APP sensor. | "GRY/RED", "RED" and/or "BRN" wire is shorted to ground circuit. |