184000693 - 5040BC CLIMATE CONTROL COMPRESSOR LINEAR SENSOR ON/OFF CHECK
Disconnect the electrical connection for the linear sensor.1, Earth2, Power supply3, SignalConnect a linear potentiometer (end of scale 1 KOhm, previously positioned at around 500 ohm between the centre pin andone of the side ones) to the pins of the linear sensor electrical connector.
Place the key in the ON position.Using a multimeter, check that the voltage between pins 1 (earth) and 3 is around 2.5V.Switch on the engine and switch on the air conditioning using the special switch located on the climate control system control unit.The climate control system should come on normally in these circumstances.Alter the potentiometer resistance until the voltage reading on the multimeter between pins 1 (earth) and 3 is about 0V.The air conditioning system should switch off in these conditions because the engine management node receives low circuit pressure information.Alter the potentiometer resistance until the voltage reading on the multimeter between pins 1 (earth) and 3 is about 4.6V.The air conditioning system should switch off in these conditions because the engine management node receives high circuit pressure information.Connect the recharging device to the air conditioning system in order to read the low pressure (1a) and high pressure (1b) values.
Start the engine and run it at idle speed.Deactivate recirculation (led on button off).Press the fan speed increase button until 12 bars are showing on the display.Turn the temperature knob until it is at the coldest setting (LOW).Deactivate the compressor by pressing the appropriate button (both temperature displays should flash)Check on the recharging device's low and high pressure gauges, that the pressure is within 5 bars for an ET of about 20°C, and about 6 bars for an ET of about 30°CActivate the air conditioner (led on compressor activation key on).Check that within 1 minute the pressure reaches 2.5 - 3 bar on the low pressure gauge and 15 - 16 bar on the high pressure gauge.Wait for the engine cooling fan to come on.Check that the pressure reaches 1.5 - 1.8 bar on the low pressure gauge and 10 - 12 bar on the high pressure gauge .Check that the engine cooling fan goes off when the high pressure drops to 11-12 bars.
