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 750iLFACTORY OEM SERVICE PROCEDURE
Control Units/Modules
CONTROL UNITS/MODULES LOCATION
| Component | Location |
|---|---|
| Automatic Heating & A/C Control Unit | Between front footwells, ahead of plenum. |
| ABS Electronic Control Unit | Behind right front shock tower, in E-Box. |
| ABS/ASC Electronic Control Unit | Behind right front shock tower, in E-Box. |
| ABS/ASC + T Control Unit | Behind right front shock tower, in E-Box. |
| Anti-Theft Module | Below left side of rear seat, ahead of power distribution box. |
| Check Control Module | In front power distribution box. See Figure . |
| Chime Module | Under left side of dash, on hush panel. |
| Cruise Control Module | Behind right front shock tower, in E-Box. |
| Crash Control Unit | In front power distribution box. See Figure . |
| Electronic Damper Control Unit | At right side of luggage compartment. |
| Electronic Transmission Control Unit | Behind right kick panel. |
| EML (1.3) Electronic Control Unit | Behind right front shock tower, in E-Box. |
| EML (1.7) Electronic Control Unit | Behind right front shock tower, in E-Box. |
| General Module | In rear power distribution box. See Figure . |
| Headlight/Foglight Module | On left side of engine compartment, in auxiliary fuse/relay box. See Figure . |
| Infrared Locking Control Unit | In rear power distribution box. See Figure . |
| Lamp Control Module | In front power distribution box. See Figure . |
| Lock Sensor Control Unit | Behind left kick panel, on module/relay bracket. |
| Motronic Control Unit I | Behind right front shock tower, in E-Box. |
| Motronic Control Unit II | Behind right front shock tower, in E-Box. |
| Mute Accessory Module | At right front of luggage compartment, near phone transceiver. |
| On-Board Computer | Right of radio. |
| Rear Headrest Control Unit | In rear power distribution box. See Figure . |
| Relay Module | In rear power distribution box. See Figure . |
| Seat/Mirror/Steering Column Memory Control Module | Under driver seat. |
| Servotronic Control Unit | Behind left kick panel, on module/relay bracket. |
| Supplemental Restraints System Diagnostic Module | Behind left side of dash, left of steering column. |
| Wheel Camber Control Unit | Under vehicle, above axle. |
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.