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
Powertrain Control Module (PCM) Connector End View (C175B)
C175B CONNECTOR SPECIFICATION
| Pin | Circuit | Gauge | Circuit Function | Qualifier |
|---|---|---|---|---|
| 1 | * | * | not used | |
| 2 | 325 (DB-OG) | 20 | Starter relay control | |
| 2 | 32 (RD-LB) | 20 | Starter relay control | Late production |
| 3 | 330 (YE-LG) | 20 | Power steering pressure switch signal | |
| 4 | * | * | not used | |
| 5 | * | * | not used | |
| 6 | * | * | not used | |
| 7 | 1093 (TN-RD) | 20 | Power, Hot in Start with Park or Neutral | 3.0L |
| 8 | 511 (LG) | 18 | Brake pedal position switch feed | |
| 9 | 791 (RD-PK) | 20 | Fuel tank pressure transducer sensor signal | |
| 10 | 570 (BK-WH) | 18 | Ground | |
| 11 | 1908 (WH) | 20 | High speed CAN bus + | |
| 12 | 926 (LB-OG) | 20 | Fuel pump control | |
| 13 | 91 (VT-WH) | 20 | EVAP canister vent solenoid, control | |
| 14 | * | * | not used | |
| 15 | 198 (DG-OG) | 20 | Dual pressure switch signal | |
| 16 | * | * | not used | |
| 17 | 3850 (LG-VT) | 20 | Low speed fan control relay control | |
| 18 | * | * | not used | |
| 19 | * | * | not used | |
| 20 | 470 (PK-BK) | 20 | Intake air temperature sensor signal | |
| 21 | 238 (DG-YE) | 18 | Fuel pump monitor | |
| 22 | * | * | not used | |
| 23 | 1909 (BK) | 20 | High speed CAN bus - | |
| 24 | * | * | not used | |
| 25 | 331 (PK-YE) | 20 | A/C clutch relay control | |
| 26 | 347 (BK-YE) | 20 | Dual pressure switch signal | |
| 27 | 665 (OG-YE) | 20 | Overdrive cancel switch signal | |
| 28 | * | * | not used | |
| 29 | * | * | not used | |
| 30 | * | * | not used | |
| 31 | 167 (BR-OG) | 20 | TX signal | |
| 32 | 967 (LB-RD) | 20 | Mass Air Flow (MAF) sensor signal | |
| 33 | * | * | not used | |
| 34 | 191 (LG-BK) | 20 | Vapor management valve control | |
| 35 | 100 (WH-RD) | 20 | PCM power relay output | |
| 36 | 100 (WH-RD) | 20 | PCM power relay output | |
| 37 | * | * | not used | |
| 38 | 228 (DB) | 20 | High speed fan control relay 1 control | |
| 39 | 386 (LB) | 20 | Cooling fan relay control | |
| 40 | 351 (BR-WH) | 20 | Reference voltage | |
| 41 | 359 (GY-RD) | 20 | Signal return | |
| 42 | 168 (RD-BK) | 20 | RX signal | |
| 43 | 968 (TN-LB) | 20 | Mass Air Flow (MAF) sensor, signal return | |
| 44 | 107 (VT) | 20 | Flash/EEPROM power supply | |
| 45 | 16 (RD-LG) | 20 | Voltage supplied at all times (overload protected) | |
| 46 | * | * | not used | |
| 47 | 57 (BK) | 18 | Ground | |
| 48 | 57 (BK) | 18 | Ground | |
| 49 | 57 (BK) | 18 | Ground | |
| 50 | 1202 (BR-LG) | 18 | Signal return | 3.0L |
| 50 | 1202 (BR-LG) | 20 | Signal return | 2.3L |
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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