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.
2004 Mercury MontereyFACTORY OEM SERVICE PROCEDURE
Powertrain Control Module (PCM) C175a
WARNING: This page is about a different car, the 2004 Lincoln LS. However, it is still accessible from the selected car via links, so may be relevant.
POWERTRAIN CONTROL MODULE (PCM) C175A PINS DESCRIPTION
| Pin Number(s) | Circuit Designation/Description | Normal Condition/Measurement |
|---|---|---|
| 3 | 4-RE8 (GY) SCP communication circuit | Less than 5 ohms between the PCM and the DLC. Greater than 10,000 ohms to ground with all network modules disconnected. |
| 4 | 5-RE8 (BU) SCP communication circuit | Less than 5 ohms between the PCM and the DLC. Greater than 10,000 ohms to ground with all network modules disconnected. |
| 53 | 4-EC7 (GY/RD) SCP communication circuit | Less than 5 ohms between the PCM and the DLC. Greater than 10,000 ohms to ground with all network modules disconnected. |
| 54 | 5-EC-7 (BU/RD) SCP communication circuit | Less than 5 ohms between the PCM and the DLC. Greater than 10,000 ohms to ground with all network modules disconnected. |
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.