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.
1991 BMW M5FACTORY OEM SERVICE PROCEDURE
Control Units
CONTROL UNITS LOCATION
| Component | Location |
|---|---|
| ABS Electronic Control Unit | In E-Box. |
| ABS/ASC Electronic Control Unit | In E-Box. |
| A/C Compressor Control Unit | Under left kick panel. |
| Air Intake Control Unit. | In E-Box. |
| Anti-Theft Module | Below left rear seat. |
| Check Control Module | In front power distribution box. See Figure . |
| Chime Module | Under left side of dash. |
| Crash Control Unit | In front power distribution box. See Figure . |
| Cruise Control Module | In E-Box. |
| DME Control Unit | In E-Box. |
| EGS Control Unit | Under right kick panel. |
| EML Control Unit | In E-Box. |
| General Module | In rear power distribution box. See Figure . |
| Infrared Locking Control Unit | In rear power distribution box. |
| Integrated Climate Regulation II Control Unit | Below center of dash. |
| Lamp Control Module | In front power distribution box. See Figure . |
| Memory Seats/Mirrors Control Unit | Under left front seat. |
| On-Board Computer | At center of dash, right side of radio. |
| Relay Module | In rear power distribution box. See Figure . |
| Servotronic Control Module | Inside left kick panel. |
| Supplemental Restraint System Diagnostic Module | Below left side of dash, at left side of steering column. |
| Wheel Camber Control Unit | Near rear differential. |
Factory Service Tools
Use the Manual With the Right Hardware
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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.