C5 X7 weak aircon flow

[aranciata-oz]

Hi there,

Firstly just to say I’ve searched high and low in this forum and others, to see if this problem has been reported (and hopefully solved) before but no luck …

My mid year purchased MY14 Exclusive Tourer’s aircon has generally been fine during winter but today’s hotter weather revealed a problem that I suspect has already been there … the aircon flow even on override manual highest speed, is worryingly weak … it’s equivalent to the No. 2 fan speed setting at best for almost every other Jap/Korean car I’ve owned …

At first I thought the fan speed was potentially stuck on the half or first clover leaf (out of 4 leaves) speed, but as I dialed up the fan speed I could feel a distinct but terribly faint increase in air flow - except there’s hardly any flow at the full speed! Is this normal? Surely not! The rear B pillar vents also hardly had any flow even if they were discernible. My kids were astounded given hot interior needed a fast cool-down and “mummy’s i30 has no problem like this!”

Where do I begin my investigations? Even though I’m a mechanical engineer, aircon systems have often stumped me …

I’m quite happy to have an aircon specialist work on this thing but I would first like to diagnose/test things myself, perhaps even a blocked cabin filter etc … any pointers appreciated … thanks.

 

[Ken W]

I'm sure this has been mentioned before but the pollen filter seems to get clogged and really limit the air flow. So look up how to change the pollen filter and you will be amazed at the improvement in air flow. I will be putting the third filter into my car in the next week or so in preparation for summer. Here is a thread link below that talks about changing the pollen filter. I have not removed the glovebox on later changes as it doesn't really help much - you just have to squash and bend the new filter to get it in.

Pollen replacement C5

Morning people Quick question about replacing the pollen filter, is it something that can be easily replced or should it be left to the mechanic? If it is indeed easy to do where is the best place to obtain replacement etc. details 2008 exclusive C5 X7 Cheers

www.aussiefrogs.com

Cheers, Ken

 

[seasink]

The hardest part by far is twisting your body around on the floor.

The filter door is on the passenger's side under the metal AC refrigerant pipes, which divert over it.

 

[Dijon16]

There´s heaps of info on this.

Can you confirm that when you went to increase the fan speed, that it did actually sound like it was turning faster?

What were the vent direction settings - foot, middle or top?

Where in Sydney are you? If you are near the northern beaches, I can show you how to do it, once I take my contortionist lessons.

 

[aranciata-oz]

You lot are legends - thanks so much. Just today I bought a cabin filter online - not sure if this is separate to the pollen filter? Anyway let me look up the resources you’ve pointed me here @Ken W.

@seasink - yes I will give my body a good stretch before contorting so not to trigger my back issues .

@Dijon16 - yes I could hear the fan was blowing faster as I cranked up the speed. The vent direction setting was purely face level (middle) when I manually set the fan speed to max. I went back to the drivers manual again today and it did recommend to shut the top dash vent on a hot day, which I did, but it made little difference to airflow. Thank you for the offer to assist - I’m down in the shire. Let me try replacing it myself first …

 

[jaahn]

You lot are legends - thanks so much. Just today I bought a cabin filter online - not sure if this is separate to the pollen filter? Anyway let me look up the resources you’ve pointed me here @Ken W.

@seasink - yes I will give my body a good stretch before contorting so not to trigger my back issues .

@Dijon16 - yes I could hear the fan was blowing faster as I cranked up the speed. The vent direction setting was purely face level (middle) when I manually set the fan speed to max. I went back to the drivers manual again today and it did recommend to shut the top dash vent on a hot day, which I did, but it made little difference to airflow. Thank you for the offer to assist - I’m down in the shire. Let me try replacing it myself first …

Just a comment additional to the other good information. I found years ago my C5 would ice up the system occasionally in very high humidity. So it would go OK but 'die-off' after a while. The cure was to switch of for a couple of minutes to allow the ice blockage to melt and then restart. Only happened occasionally. I might think if the filter was blocking air flow it might happen easier.
Jaahn

 

[DStary]

I literally just did a cabin filter replacement myself in an X7 (also a 2014 tourer)! I hope it solves your problem. Mine wasn’t too bad and I had no climate control issues, but I didn’t know the filter condition, so decided to swap it out.

Honestly, it was probably no more than a 10 minute job (may have been closer to 5), and most of that was carefully getting the new one in. I removed the trim above the passenger’s feet, and unplugged the footwell light, and the rest wasn’t too bad at all. Getting the new part in involved a little inserting, retracting, inserting, retracting etc, but it seated in quite nicely in the end. Good luck with yours!

 

[Dijon16]

I agree with DStary. Anything is easy once you know how. There is only about 10 mins worth of work in it, what takes time is seeing things for the first time and getting in the right position.

You can put a pad on the ground and reach in the passenger footwell, or put the seat back down and lie on it with your head in the footwell, but you lose some shoulder rotation then.

From memory the cover just clips off, maybe a tab at the bottom. If this was a Haynes manual it would say that fitment is the reversal of removal. In theory, yes. The old one comes out relatively easily, the new one does have to be jiggled and wiggled around the heater pipes.

Ensure that it is the correct orientation, and push home fully or the cover will not go back on.

 

[aranciata-oz]

Thanks everyone for all your advice - I replaced the under dash cabin filter an hour ago - wasn’t too difficult but I do have pretty dexterous skills.

Unfortunately when I pulled out the filter I saw something I didn’t want to see - a relatively unclogged filter! It appears the filter was probably replaced at some point but definitely was not the original one …

I went ahead and installed the new filter (Mann) one anyway and yeah to my disappointment the airflow even on face level only and at full blast, wouldn’t blow the rice off a pudding (trying to find a French cuisine equivalent but too annoyed to think!).

I’m lost where to investigate next - the blower motor?

 

[Ken W]

Sorry to hear that. You will need to do some testing. I suggest you take the filter out and see how much air blows out of the slot with the cover off. That should give you an indication of whether the air entry is blocked or the fan is poor. If that is OK, see if you can tell if all the flaps in the air treatment box are working properly. If you have one of those USB cameras on the end of a bendy wire, you could stick that in the slot and see if you can see the evaporator to check if it is blocked to air flow and/or watch any of the flaps moving.

These units have coolant flow through the heater element all the time but close it off and open the evaporator air circuit when interior temperature is more than that on the climate control dial. Is the airflow poor in both modes?

Let us know how you go.

Cheers, Ken

 

[seasink]

Here you are for this evening's consolation - https://cuisine.journaldesfemmes.fr/recette/319945-riz-au-lait-vanille-et-cannelle

The fan motor is above the filter and can be removed enough to see if it runs well and at varying speeds. It has a controller, also on the side of the unit.

Did you test the fan in heating mode or cooling? The filter is to protect the coils more than provide comfort. Cooling (evaporator) coils get wet or icy and can block, and that is a larger AC job. You can see the coil location.

If that lot all work, there are rotating flaps, each with a motor on the unit side. These can strip at the motor flap connection. The fix is in the forum.

Long shot - if the car was parked long term under trees, it can even fill with compost under the scuttle. The scuttle drains will then block. This is fixed at the soft rubber at each end, and then pulls off, held by roller catches. You need multiple hands to push it all back on evenly.

 

[aranciata-oz]

Thanks @Ken W + @seasink - small steps for me first - with the break in rain I managed to step out to the car and pull the new filter out then ran the fan manually again with temp at 21 (this morning I ran it at Lo with the same effect) - as I expected the airflow was still very small. When daylight returns I will look a bit deeper at your fan motor investigations @seasink - thanks.

 

[aranciata-oz]

This is good @seasink - you’re a treasure trove! https://cuisine.journaldesfemmes.fr/recette/319945-riz-au-lait-vanille-et-cannelle

 

[aranciata-oz]

Here you are for this evening's consolation - https://cuisine.journaldesfemmes.fr/recette/319945-riz-au-lait-vanille-et-cannelle

The fan motor is above the filter and can be removed enough to see if it runs well and at varying speeds. It has a controller, also on the side of the unit.

Did you test the fan in heating mode or cooling? The filter is to protect the coils more than provide comfort. Cooling (evaporator) coils get wet or icy and can block, and that is a larger AC job. You can see the coil location.

If that lot all work, there are rotating flaps, each with a motor on the unit side. These can strip at the motor flap connection. The fix is in the forum.

Long shot - if the car was parked long term under trees, it can even fill with compost under the scuttle. The scuttle drains will then block. This is fixed at the soft rubber at each end, and then pulls off, held by roller catches. You need multiple hands to push it all back on evenly.

View attachment 211026

@seasink - quick question - can the motor be easily accessible from the front passenger compartment ie just further up from the filter compartment? Or is it accessible only from the engine bay (I think I saw a video where the guy accessed it from there).

Due to the wet weather and still awaiting my USB endoscope camera to be returned, I did quickly test the fan whilst driving today and can confirm the footwell and upper dash vents blow pretty well when on max, just not the face vents (including the B pillar vents). So if I can be pointed to where I can inspect the flaps and motor that would be a awesome (I just looked in this forum but not sure if the search entries I made was accurate enough as it wasn’t returning what I want).

Thanks

 

[seasink]

That suggests that you'd get quite a performance from the screen demister, that runs the fan on maximum.

The flap motors are on the passenger's side of the unit. They have splined shafts which engages in an internal plastic spline on the rotating flap (like a half cylinder). The plastic can strip. It is a recurring subject in the forum.

 

[seasink]

Here are images of the heater side with fan and flap motors removed, and a pair of replacement flaps, both from ads. The internal splines are visible. This principle has been used for a while on several makes. It is also possible to strip an internal gear in the motor, so check they turn when the temp is changed.

 

[aranciata-oz]

Here are images of the heater side with fan and flap motors removed, and a pair of replacement flaps, both from ads. The internal splines are visible. This principle has been used for a while on several makes. It is also possible to strip an internal gear in the motor, so check they turn when the temp is changed.

View attachment 211089

View attachment 211088

Thanks so much @seasink - seeing the internal splines now, makes sense.

Now … after much family events getting in the way (struggling with inefficient aircon on a hot day not being one otherwise I would have been pushed to fix this!), I finally managed to stick my head back in the passenger footwell compartment again this morning, but not much luck with the endscope camera as the only inlet I could find to stick the gooseneck camera was, the foot vent. There appeared to be some yellow rods in there (first pic) - I’m probably looking in the wrong area but I was trying to direct the camera into the flaps, then have someone else operate the aircon vent modes to check the flaps operation … anyway I’m getting nowhere here (more a reflection on my lack of knowledge!) so I’m left with a few of big questions …

1 - where can I stick the camera to have a decent view of the flaps operating completely?

2 - realistically if it’s motor related (refer to further testing I did below), surely the whole dashboard will need to be removed to access this vent unit? I’m depressed about this as this will mean a huge chunk of my time out as well as an immobile car.

3 - first of all though, to check if the motor/flap splines are OK, is it just a case of unscrewing the motor’s screw to the housing (pic 3) then disconnecting it and pulling it straight out?

Speaking of further testing, as it was a relatively warm day when I set off earlier, the aircon set at 21deg went into max fan mode to conduct a series of tests again:

- I could tell even at exclusive top or bottom vents only, the airflow wasn’t great - the fan noise was muted at best, not the sort of loud gushing I’m used to in other cars. It almost seems like the fan is running at half pace at all its individual fan speed settings.

- at full fan speed, when I’ve individually changed the vent modes from exclusively top to exclusively face then exclusively feet, I can tell the flaps are probably working (both drivers and passengers) as the airflow changes after 5secs. Just half paced airflow!

So my next steps are to pull out that first motor and check the splines … I’m really hoping I don’t have to spend 2+ days removing the dash just to get to the vent unit to be able to troubleshoot it properly (not to mention waiting for parts!). If someone can confirm that’s how you pull the motor out, that could be decent traction for me … thanks.

 

[seasink]

Flaps usually stops flow to one side, or won't give hot, things like that. The view of them is through those outlets on top, and that means partial dash front removal. You can replace them from there.

Does windscreen defrost produce a blast?

Have you run the fan motor out of the unit?

If the motor works, is there flow through the heating and cooling coils?

 

[Ken W]

If you take the wiring connector out of the speed controller (located just under the heater pipes), that will give you access to the motor wires. There are two clips either side that need to be held against the conncetor block to get the connector to release. If you turn on the ignition you will find the ?red wire at one end of the connector has 12 volts and the black wire at the other end is grounded to chassis. The motor will run at full speed if you connected second ?red wire beside the 12 volt wire to the ground wire. Expect a big spark if you link those up with the ignition on.

Is the motor speed greater than you get through the aircon speed control? If so you may have dodgy fan speed controller.

On our C5X7, if you push the auto button, the fan noise is so loud, it is difficult to talk to other people in the car.

Cheers, Ken

 

[aranciata-oz]

Flaps usually stops flow to one side, or won't give hot, things like that. The view of them is through those outlets on top, and that means partial dash front removal. You can replace them from there.

Does windscreen defrost produce a blast?

Have you run the fan motor out of the unit?

If the motor works, is there flow through the heating and cooling coils?

Thanks @seasink. Let me look up how to do a partial dash removal. I've seen videos of it and having removed dashes in other cars before I imagine it wouldn't be too intimidating but the balance I'm trying to strike here is not having to do this until all the low lying fruit diagnoses can be done first because ultimately I don't have that much room to have the car incapacitated for too long ...