Theory and Operation: Theory/Operation: Relays
- Fuel Pump Relay: See FUEL PUMP RELAY under FUEL SYSTEM in this article.
- Main Relay: See MAIN RELAY under INPUT DEVICES in this article.
- Oxygen Sensor Heater Relay: See OXYGEN SENSOR HEATER RELAY under EMISSION SYSTEMS in this article.
RELAY LOCATIONS
| Relay | Location | |
|---|---|---|
| Fuel Pump Relay | ||
| 3 Series | On Bracket On Left Front Shock Tower (Center Relay On Bracket) | |
| 5 & 7 Series | In Relay Box In Right Rear Corner Of Engine Compartment | |
| 635CSi | On Left Side Of Engine Compartment, Attached To Outside Of Relay/Fuse Box. | |
| Main Relay | ||
| 3 Series | Left Front Shock Tower | |
| 5 & 7 Series | In Relay Block, Behind Right Front Strut Tower | |
| 635CSi | On Outside Of Relay/Fuse Box On Left Side Of Engine Compartment | |
| Oxygen Sensor Heater Relay | Behind Right Front Strut Tower | |
| Starter Relay | Left Rear Of Engine Compartment | |