Climate Control Module (CCM) Cleaning/Servicing - a word of warning...

[JamesT5]

I seem to be making up for a lack of posts over the last few months, those of you who follow my facebook updates will be pretty much up to speed on all of the mishaps and changes, but for the rest of you who aren't, here was another costly mistake of mine. Some of you will be well aware of this potential problem for one reason or another but for those less technically minded (like myself), a word of warning when servicing or cleaning the CCM.

Some background... Since I had the car the button for directing the air flow to the feet had been 'stuck inwards' (see photo) and was jammed, no matter what I did it wouldn't release so I decided to take the damn thing out, dismantle it and sort this annoying issue once and for all. Once I'd fiddled about and worked out how to fix it, I also decided to clean the fluff out of that temperature sensor grill on the front of the unit as well as clean the fan up inside as well because it was clogged with dust and was annoying me also.





So I found out that the button was jammed in because some plonker had managed to get some brown sticky substance in the button at some point, possibly a coffee or something judging by the colour of it. I managed to clean it all out and put the buttons all back together nicely, then put the circuit board back in before turning my attention to that dusty aperture leading to that grill thing on the front.



Now, me being me, I decided to poke a screwdriver through and gently prise out the dust. Big mistake! I ended up snapping the little thermistor in there just behind the grill and the result of this should you ever do it is a total failure of your CCM (as I quickly found out myself).



So, after kicking myself for a few hours and trying to fruitlessly resolder the damn thing (which is also pointless by the way but I was desperate), I conceded defeat, hopped on to fleabay and purchased a replacement unit using the part number on my old one.

The unit turned up a couple of days later and was basically the same apart from the buttons on the bottom were missing on the new unit (see photo - the original casing is the top one of the two). As swapping the buttons over would involve removal of the circuit board anyway, I decided it might just be easier to swap over the circuit board as this was identical and the thermistor it soldered to the board.



10 - 15 minutes of careful 'surgery' and I swapped the innards of the replacement unit over to my old casing and then refitted it to the car. Hey presto! No software update or VIDA reset needed and I had a working CCM again.



There we have it, a word of warning to you anyone thinking of doing this themselves. If I can replace the thermistor in the old circuit board then I'll have a unit that I can sell on, if not it will be scrapped or I'll keep the casing as a spare.