Renault Koleos Service Repair Manual: Air conditioning: Check

I - MEASURING DEVICE PREPARATION OPERATION

• Check that the dual temperature sensor measuring device operates correctly (refer to the instruction manual for the device).
• Adjust the unit of the value displayed in ºC.
• Adjust the reading accuracy of the device to 0.1ºC.

Adjust the reading mode to (ΔT) = (T1 - T2)

• Check the two sensors T1 and T2 in order to calculate the correction (Δ) to be applied to the measurement (ΔT) = (T1 - T2). the two sensors must indicate the same measurement under the same conditions.

  Check the sensors:

  • bring the two ends of the sensors together until they touch,
  • place them in the air flow of an air vent,
  • set the passenger compartment blower unit to maximum speed,
  • wait for the value to stabilise,
  • note the correction value (Δ).

II - VEHICLE PREPARATION OPERATION

• Position the vehicle away from direct sunlight in an area with a stable ambient temperature greater than or equal to at least 15ºC.
• Close the bonnet.
• Open the front windows.
• Run the engine at idle speed.
• Set the heating and ventilation controls as follows:
  • recirculation mode in the external position,
  • air distribution in "face" mode,
  • temperature adjustment control in maximum cold position in the front (and the rear if equipped),
  • passenger compartment blower unit speed in maximum position (cut off the rear control if equipped),
  • front centre and side air vents open, with vanes set to neutral position,
  • the air conditioning system must be activated (indicator light on).
• Wait 5 minutes with the engine idling before taking any measurements.

III - MEASUREMENT

• Record the air temperature at the scuttle panel grille (T3).
• Depending on the vehicle, open the bonnet to access the scuttle panel grille.
• Place the sensor where air is drawn through the scuttle panel grille.
• Wait for the value to stabilise.
• Note the value of temperature (T3).
• Close the bonnet if it was opened.

• Record the air temperature at the left-hand air vent (T1), and the air temperature at the right-hand air vent (T2).
  • Fit sensor T1 in the left-hand air vent.
  • Fit sensor T2 in the right-hand air vent.
• Note the temperature differences, once the value (ΔT) has stabilised:
  • Between T3 and the higher of values T1 or T2, (T3 - highest value).
  • Note this temperature difference.
  • Between T1 and T2 (read the value (ΔT) in the reading display mode (T1 - T2)).
  • Note the temperature difference (ΔT) according to the correction (Δ) to be applied to the measurement.
• If the measurement (ΔT) = (T1 - T2) is unstable, carry out the following procedure:

• Force operation of the engine cooling fan by adjusting the engine speed.
  • Stabilise the engine speed at 2000 rpm while T1 and T2 temperature measurements are being recorded.
  • Check that the engine cooling fan assembly is operating.
  • Record the temperatures by following the instructions given in the MEASUREMENTS paragraph.

IV - FAULT FINDING

• It is essential to observe the following two conditions:
  • The difference between T3 and the highest value of T1 or T2 should be greater than or equal to 5ºC,
  • The difference between T1 and T2 must be less than or equal to 2ºC.