CCM gremlins || 2008 - V70 III 2.0

[rafa226]

Hello

After water infiltration inside the car, i encounter a few problems and i would need an advice :

- blower fan do not work, but LED is okay on the CCM panel
- rear defrost does not work and no LED, but it sometimes works after driving for a long distance
- air flow distribution servo motors and the air recycling flap do not work when I operate the buttons on the central panel
- air con. seems to engage properly because when i switch it on/off i can hear the engine changing its speed., but of course no air flowing
- fuses all checked and OK

After a few thinking, i suspect that the CCM has electrical gremlins that may cause all those problems, because it is upstream of all those peripherals.
Do you think i could be on the right way, or is my theory unfounded ?

Thank for your advices !

Raphael

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[xHeart]

After water infiltration inside the car, i encounter a few problems and i would need an advice :

Comment l'eau est-elle entrée ?

[rafa226]

The water came in through the top of the windshield:
On each side of the windshield, there are gutters, and they were clogged (Sahara dust that we have sometimes in south of France when rains comes from the south).
It snowed, the snow stayed on the car for 2 days, and when it melted, the water seeped in through the top windshield seal...

So the water dripped from the car's ceiling light, and i am pretty sure, ONTO the CCM.

This afternoon, I removed the climate control unit and cleaned it with contact cleaner. Without any effect. But I was able to observe that it had gotten wet.

[xHeart]

This afternoon, I removed the climate control unit and cleaned it with contact cleaner. Without any effect. But I was able to observe that it had gotten wet.

The Cabin Air Temperature Sensor is a key component in CCM.
The small fan inside the assembly draw the air in, passes the sensor, for CCM function properly - else expect a malfunction.
See items #18 in this diagram:


... here is a close up

[rafa226]

Thank you for your answer. I have seen this little guy, and did my best to clean it without damage because it's so tiny !
A few days ago i've red a topic about the possibility to replace it's thermistor, and, as you say, many malfunctions that could appear because of it.
The specs seems to be 10KΩ @25°C and it's pretty cheap

It surely could explain the blower problems, but do you think it could be involved in the rear defrost LED not working ?

[xHeart]

It surely could explain the blower problems, but do you think it could be involved in the rear defrost LED not working ?

I had issue with recirc LED; which resolved itself after the CCM service - blower fan and thermistor clean up.

The vent collects direct and fuzz build up, it blocks thermistor and obstruct the blower fan. You can place one end of a hose over the vent and other to your ear; with ignition on (not engine running) you can hear the good fan run. Be careful - it's fragile.

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[rafa226]

You can place one end of a hose over the vent and other to your ear; with ignition on (not engine running) you can hear the good fan run. Be careful - it's fragile.

Thank you for this great tip, i will try it !

Also, i noticed there was the same vent in the dome light, do you know if it's the same purpose ?

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[rafa226]

Finally I ordered a CCM with matching numbers on ebay, replaced it and everything blows hot again!
I am so happy, now I have to fix this leaking windshield!
Thanks.