C5 2, 2007 reg. interior temperature sensing fan

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MJM
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Re: C5 2, 2007 reg. interior temperature sensing fan

Post by MJM »

A bit more info.
Cleaning the cabin sensor seems to have helped a little but it is a bit hard to tell.
went on a decent run yesterday to get some parts for my Triumph Spitfire (it's a bit simpler than the c5 to work on!). On the way back my mate in the passenger seat started to fry but my side was ok, not as cool as usual, though. I searched the forum for heater flap failure and removed the air mix control motor. I knew that the motor was working because I had cycled it using the Lexia. I cycled it again when it was in the open and it was fine. The end of the control flap appeared to have retreated a little into the heater box so I thought that perhaps the drive from the motor had become separated from it. I managed to pull the end of the flap back into place, made sure that the drive was engaged and tried it again. No luck. I removed the motor and saw that the flap connector had'nt moved. I tried to turn the flap to see if it was free and was rewarded with the flap end dropping into the heater box! At least I now knew the problem.
I have a flap repair kit on order. I intend to access the heater box by cutting into the side. There are several videos on line showing how to do it and it doesn't seem to be too arduous. (famous last words).
i will wait until the kit arrives to get a better idea of where and how much to cut.
Does anyone want me to photograph the procedure?
After repairing this problem then I will have a better chance of seeing if the heating system is ok.

Malcolm.

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GiveMeABreak
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Re: C5 2, 2007 reg. interior temperature sensing fan

Post by GiveMeABreak »

I think I've mentioned that as a possibility on several posts - Lexia may report it ok as the motor is perfectly fine and working - but the plastic gearing wears out and finally just turns leaving the flap in the last state. That test really only rules out the stepper motor Malcolm, which unfortunately leaves the dreaded gearing issue.

viewtopic.php?p=632667#p632667

viewtopic.php?p=516140#p516140

Good luck with the repair and if you have the time and inclination, I'm sure it would also be very useful for other members to see Malcolm :)

MJM
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Posts: 134
Joined: 20 Aug 2008, 12:49
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Re: C5 2, 2007 reg. interior temperature sensing fan

Post by MJM »

The job's done.
I now have independant left and right temperature control.
I forgot about photographing the event but the forum posts and links were sufficient, thanks to contributors.
A couple of notes:-
I had the new flap to hand and holding it up to the heater box in both its cold and hot positions gave me a good idea of where to cut the box and how much. I made the top horizontal cut above the pivot point and below the back motor fixing screw so that the motor is well located and held on the un-butchered part of the duct.
The actual operating position of the flap is well inside the box, and it drops into a well. (some idea of this can be had from the length of the spindle before the flap actually starts. This means that the cuts have to go deeper into the box than it first appears. there are a couple of wiring looms and a sensor under the bottom of the box which need to kept clear of.
I had a look into the box while I could and sprayed some ptfe lubricant around all the pivots that I could see.
Revell contacta professional plastic model kit glue held the cut pieces back together ok.

I think the air-con may be low on refrigerant because the air still seems a bit warmer than it used to. I need to take the car on a run to be certain. That's a job for another day.