Land Rover Repair: 02 Disco clicking noise on startup, engine coolant, heater assembly

Question
Hi, i have a 2002 range rover 4.6 HSE (last of the old shape)when i start the engine i get a loud plastic clicking noise. It appears to be coming from under the steering wheel/foot pedel area. It happens when th A/C is switched on. It stops after about 10 clicks! any ideas what is causing this? Many thanks.

Answer
Hi Tim,

could be the in-car air temperature sensor.

Here's a note I found:

General
The heating and ventilation system controls the temperature and distribution of air supplied to the vehicle interior. The system consists of an air inlet duct, heater assembly, distribution ducts and a control panel. An outlet vent is incorporated at the rear of the cabin. Some diesel models also incorporate a fuel burning heater (FBH) system in the engine coolant supply to the heater assembly.

Fresh or recirculated air flows into the heater assembly from the inlet duct. An electrical variable speed blower in the inlet duct, and/or ram effect, forces the air through the system. Depending on the settings on the control panel, the air is then heated and supplied through the distribution ducts to fascia and floor level outlets.

I hope this helps,

JohnMc