With the above-mentioned vehicles it can happen that, when the weather is extremely damp or humid and when a journey is particularly long, the air-conditioning system will only blow out warm air.
If the air-conditioning system is switched off for 10-15 minutes, it will then function normally again for a certain amount of time.
An incorrectly sealed evaporator temperature sensor is the possible cause.
The evaporator can freeze up because of air infiltrating and the resultant faulty measured values.
To remedy the problem, the temperature sensor, which, for example, in the E90/91/92 is accessible from the front passenger footwell, should be removed and sealed. The cover below the glove compartment is
first to be removed
(Figure 1). The sensor, located on the right side of the evaporator box, can now be seen (Figure 2).
Then proceed as follows:
Make sure that the sensor's measuring cell is not covered over (Figure 4)
Figure 1
Figure 2
Figure 3
Figure 4
Important safety note
Technical information and practical tips have been compiled by HELLA in order to provide professional support to vehicle workshops in their day-to-day work. The information provided on this website is intended for use by suitably qualified personnel only.
Reprinting, distribution, reproduction, exploitation in any form or disclosure of the contents of this document, even in part, is prohibited without our express, written approval and indication of the source. The schematic illustrations, pictures and descriptions serve only for the purposes of explanation and representation of the instructions and cannot be used as a basis for installation or assembly work. All rights reserved.
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