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.
2003 Land Rover Range RoverFACTORY OEM SERVICE PROCEDURE
Inputs & Outputs
INPUTS & OUTPUTS
| Signals | Monitored By OBD II | |
|---|---|---|
| Transmission Control Module (Torque Reduction Request) | Yes - Bus Check | |
| Engine Coolant Temperature | Yes | |
| Intake Air Temperature | Yes | |
| Mass Airflow | Yes | |
| Oxygen Sensors | Yes | |
| Crankshaft Position/Speed | Yes | |
| Camshaft Position | Yes | |
| Throttle Position | Yes | |
| Vehicle Speed | Yes | |
| Knock Sensor | Yes | |
| Driver Demand Sensor | No | |
| Ambient Air Temperature (via CAN) | Yes (No MIL) | |
| Soak Time (via CAN) | No | |
| Fuel Level (via CAN) | Yes (No MIL) | |
| Radiator Outlet Temperature | Yes | |
| Cruise Control Switches | No | |
| Brake Pedal Position | No | |
| Transfer Gear Range (via CAN) | Yes (No MIL) | |
| EVAP System (Leak Diagnosis Module - Pump Motor Current) | Yes | |
| Output Signals | ||
| Transmission Control Module | Yes - Signals Checked Separately | |
| Throttle Actuator | Yes | |
| Ignition Coils | Via Misfire Monitoring | |
| Injection Valves | Yes | |
| Secondary Air Injection Pump & Valve | Yes | |
| EVAP Canister Purge Valve | Yes | |
| Switching Valves (Variable Camshaft Timing) | Yes | |
| Malfunction Indicator Lamp (MIL) (via CAN) | Not directly | |
| EVAP System (Leak Diagnosis Module - Pump Motor & Solenoid Valve) | Yes | |
| EVAP System (Leak Diagnosis Module - Heater) | Yes (No MIL) | |
| Oxygen Sensor Heating | Yes | |
| Fuel Pump Relay | No | |
| Air Conditioning Compressor Relay | No | |
| Auxiliary Engine Cooling Fan | No | |
| Thermostat Heating Element | No | |
| Engine Starter Relay | No | |
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.