Instructions on Replacing the ECU Unit in a Range Rover
- 1). Disconnect the negative battery cable from the battery using a 1/2-inch wrench to loosen the clamp bolt on the terminal end. The battery in the Range Rover is located in the passenger side front of the engine compartment.
- 2). Remove the plastic door sill plate on the passenger side of the vehicle by pulling up on the plate until it unsnaps from the door sill. Remove the screws that attach the passenger side kick panel under the dash using a Phillips screwdriver.
- 3). Squeeze the locking clips on the wiring harness connectors and pull them straight out of the end of the old ECU located behind the kick panel. Remove the small screws that attach the ECU bracket to the body of the vehicle and slide the ECU from the bracket.
- 4). Slide the new ECU into place in the bracket and reinstall the screws. Reinstall the electrical connector by pushing them into the ECU until they snap into place. Reinstall the kick panel and door sill plate.
- 5). Tow the Range Rover to a qualified auto repair shop or dealership. Have the new ECU matched to the BCM Immobilizer (theft deterrent) signal so the engine will start.
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