C5 X7 2010 HDI heating problem

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mihkel
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Joined: 04 May 2021, 11:06

C5 X7 2010 HDI heating problem

Post by mihkel »

Hey!

I've got a 2010 C5 (X7). It's a 2.0 HDI (RHR) with the factory aux heater as well, was it Webasto?

The problem is with cabin heating when the temperatures drop below -5*C. The aux heater is working fine and starts up every time in colder weather. I get initial heating quite quickly, but it does not get warm, far from it. It takes about a 2 hour trip to feel yourself comfortable. And that is way too long. I won't even talk about colder weather.

I've checked the heater core pipes and they get hot, too hot for touch. But weirdly both supply and return pipes are hot. Both sides of the car behave the same way. Fiddling with the controls does not give any better results than auto. Is there any flaps to blame?

I've got Lexia/Diagbox to help with some diagnostics if needed. If I recall correctly then there were no faults in the climate unit last time.

And another undiagnosable problem with starting system. Once per let say 50 starts the starter cuts out in the middle of staring and the engine does not start. If it happens, it keeps cutting out before starting. Only help is to give it a little gas or disconnecting the battery for a while.
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GiveMeABreak
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Re: C5 X7 2010 HDI heating problem

Post by GiveMeABreak »

I'd be looking at your heater matrix or the air distribution mixer flap or stepper motor.
mihkel
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Re: C5 X7 2010 HDI heating problem

Post by mihkel »

As per this diagram I understand that there 2 flaps and stepper motors per side? Parts 1; 2; 3.
http://www.catcar.info/citroen/?lang=en ... BwbGllcj09

So there would be four flaps? If so - then two flaps should be leaking cold air into the vents. Is that possible?
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GiveMeABreak
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Re: C5 X7 2010 HDI heating problem

Post by GiveMeABreak »

Depends entirely on your vehicle options as to whether you have mono or dual zone Climate. I would be cautious of that website - they use old data from old offline sources that are at least 9 years old....

PSA do not provide their data to these people officially.
mihkel
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Joined: 04 May 2021, 11:06

Re: C5 X7 2010 HDI heating problem

Post by mihkel »

I've used alternatives since the "official" site went paid.

And the climate system is dual zone. Today it was -25*C. It wasn't much colder in the car. I tried recirculation which was a bit warmer. It seems to me that not enough air is passing through the vents. For information the cabin filter has been changed.
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GiveMeABreak
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Re: C5 X7 2010 HDI heating problem

Post by GiveMeABreak »

I'm just saying the info is out of date... but as long as you know this.

You have both Air Distribution and Air Mixing motors on the left and right side and an additional air intake stepper on the right side.

Diagbox should be able to confirm what is or isn't working from testing the system.
Xantippa
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Re: C5 X7 2010 HDI heating problem

Post by Xantippa »

If it blows cold in the summer normally, maybe heater matrix is blocked from coolant sealant that some previous owner has used too much?

Is outside temperature sensor ok, so it shows real temperature not too warm?