Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
2005 Mercury Mariner 3.0 1, FWDFACTORY OEM SERVICE PROCEDURE
Audio Unit Connector End View (C240A)
C240A CONNECTOR SPECIFICATION
| Pin | Circuit | Gauge | Circuit Function | Qualifier |
|---|---|---|---|---|
| 1 | 956 (OG-LG) | 16 | Voltage supplied at all times (overload protected) | |
| 2 | 137 (YE-BK) | 20 | Accessory delay relay output | |
| 3 | 19 (LB-RD) | 22 | Instrument illumination feed | |
| 4 | 57 (BK) | 22 | Ground | |
| 5 | * | * | not used | |
| 6 | * | * | not used | |
| 7 | * | * | not used | |
| 8 | 804 (OG-LG) | 20 | Tweeter, left front + | |
| 9 | 801 (TN-YE) | 20 | Speaker, left rear + | |
| 10 | 802 (OG-RD) | 20 | Speaker, right rear + | |
| 11 | 805 (WH-LG) | 20 | Tweeter, right front + | |
| 12 | 811 (DG-OG) | 20 | Tweeter, right front - | |
| 13 | 694 (BK-LG) | 16 | Ground | |
| 14 | 679 (GY-BK) | 20 | Vehicle speed signal (+) | CD6 |
| 15 | 1786 (BR-PK) | 20 | Start signal | |
| 16 | * | * | not used | |
| 17 | * | * | not used | |
| 18 | * | * | not used | |
| 19 | * | * | not used | |
| 20 | * | * | not used | |
| 21 | 813 (LB-WH) | 20 | Tweeter, left front - | |
| 22 | 800 (GY-LB) | 20 | Speaker, left rear - | |
| 23 | 803 (BR-PK) | 20 | Speaker, right rear - | |
| 24 | * | * | not used |
Factory Service Tools
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.
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