the temperature sensor is located in the passenger side door mirror it's in in that small lump at the bottom, the mirror will have to be dismantled to gain access, new sensors are available from main dealers when replacing it cut the wires close to the old sensor and solder the wires off the new sensor to the existing cables, although there is enough cable supplied to rewire it through the door it's a pain to do but make sure where you join the cables is well insulated
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