And the latest spanner in the monkey is

schlitzaugen

schlitzaugen

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The heating system.

I always thought the two dials control front and rear air temperature.

Well, today I discovered that the temperature of the air was significantly different between the left and right outlets. I felt mine were a bit cold and didn't check the passenger's. I thought it was just the engine being cold but after a considerable time, air was still cold so I checked the passenger outlets and do you know?

Toasty warm.

Now that is the kind of betrayal that makes you think your life is one big lie and you want to murder someone right there and then. Given I was by myself I put that on the to do list and I resigned to adjusting the temperature down on the left dial, which swiftly resulted in cold air being expelled by the respective outlets. No change on the right. Hmmm. Playing with the right dial had little effect, but after even more time, the air coming out in my face turned lukewarm so I could check that indeed the right dial controls the right outlets only and the left controls the left.

Alright. I'm totally ignorant about how my car works (at least partly intentionally) but now I wonder what is wrong.

Does it have two heaters and each is controlled by its own dial? Sounds complicated. Or just one heater with two separate sections? Sounds idiotic. Does it have two sets of mixing flaps, one for each dial? Still complicated but plausible. But that still means something is wrong. Given the dials feel like any jog dial I've ever come across I would hazard a guess they control some sort of stepper? servo? motors that open and close the flaps. Which would be have to be quite accurate in their movement to control that perfect mix of cold and hot air given the dials display the temperature in half a degree steps. I mean, the precision, man, the precision! Well, maybe it's just to impress the public, after all can anyone here tell what temperature their room is down to half a degree? Well, I can't.

Either way, can anyone let me know if I'm up for a new servo? Or is there some sort of brain/control module that kicked it?

Alternatively, if stupidity won over greed and there are two heaters, what sort of hell am I going to throw myself in should I decide to replace the miscreant one?

And just as I type I have this revelation. What if this is the design, a dirty conspiracy to keep the driver alert?

Screw this, I'm swapping the plugs over. Or the servos. SOMETHINGGG!

And it's cold as shit, can't put it off.

Grrrrrrack! Work under the dash. Yuck.
 
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Does everyone except me know what car you’re talking about?

Also, without wanting to cast aspersions on anyone here, you have used a couple of words that I don’t often see on aussiefrogs. Quite impressive.
 
It would help to know the car make and model, but most modern cars control the distribution with motorised flaps, which dampen or open passages through the heater. If they fail you can have temperature errors and areas or sides not responding to the controls. There is only one heater coil.

I posted a diagram of a C4 heater at https://www.aussiefrogs.com/forum/index.php?threads/c4-interior-blower-not-operating.143680/ which shows three such servomotors driving internal flaps. Many other makes use similar principles.

The common failure in PSA heaters is the flap splines stripping at the motor gears.

Attached is a section of the Renault 2003 Scenic manual (in French, sorry) with a discussion of the principles and diagnostics and the Scenic heater diagram.
renaul heater.png
 

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505604 said:
Does everyone except me know what car you’re talking about?

Also, without wanting to cast aspersions on anyone here, you have used a couple of words that I don’t often see on aussiefrogs. Quite impressive.
Click to expand...

I think its a nissan urban assault vehicle of some sort. Not a real renault, we can probably just send him away to the Japanese car forums...
 
Yeah, apologies my comrades in arms, it's a Koleos 2010.

Good point about the Nissan connection. I wonder if they used the same motor/s system?

Argh, seasink. It could be the flaps, now?!

I had a look in the manual, and yes, it is a servo motor system with a motor per flap but it look like a real nightmare to get to them. Gaaak.

I think I will just tape over the driver side outlets.
 
Yeah, thank you, seasink. That's the manual I use and it's about as useful as a kick in the teeth. I mean Haynes is funny with their helpful hints such as "take the g'box out" but this thing is on an altogether other level. It sends you to pages that don't exist, shows pictures that don't make any sense (if you can see anything at all, that is) and so on.

It does however drive home the point that working under the dash sucks.

Big time.

At least it does not mention two heater matrices. Matrixes. Matresses? Matrixecessises? Heater cores.
 
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schlitzaugen said:
It does however drive home the point that working under the dash sucks.

Big time.

At least it does not mention two heater matrices. Matrixes. Matresses? Matrixecessises? Heater cores.
Click to expand...
You probably need a mattress for comfort and relief when lying on the floor of your Nissault for a few (many?) hours.
 
I'd reckon it would cost about $2500 for a dealer to fix it. Removing and replacing the dash is a fair bit of work.
 
Hehehehe! yeah.

I think it would be more than that because they would probably replace a million other bits that didn't need replacing but they broke them on the way in plus another million bits they'll say needed replacement (but didn't) because you can't check anyway if they even replaced them.

Did I tell you that story about how my wife's car had its entire engine wiring loom replaced at a cost of 1500 bucks because there was a damaged plug that would have cost 10 bucks (okay, maybe 20, well let's say 100 bucks!) and would have taken me all of five minutes to replace? That was when she said she wanted the 405Mi16 gone.

More head scratching (read procrastination) and I am sure I'll find some crappy plastic (the actuator has a plastic arm) bit broken or something like that. Why, of why do they do this to me?!! Why go to the trouble of coming up with an expensive system with servos and computers and all that crap and then all of it relies on a plastique piece de merde to work!?! The world is going down, I tells you.

Okay, 'nuff of this. I'll go try to listen see if I can hear anything happening when I turn the dial. Hope for some motor hum or something. Hehehehe. Enough procrastination and you're bound to find something you can do without actually doing anything.
 
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Right.

Procrastination as it turn out, works.

Now I've got some good news and some not so much good news.

Switched the ignition on (no engine) and listened about, I could definitely hear the motors working (tried the left first because I knew that one worked). There's a very low buzz emanating from the side of the centre console. I then listened to the right motor and could clearly hear the same buzz happening.

Getting closer, I found where the motor is hidden so I pulled out the trim piece that runs along the centre tunnel (just pull it off with brute force), which allows you to see the motor and a very good view of the actuating arm. Now that moves nicely up and down, seems to be in one piece and even the flap arm seems to be in good order and moving as it should.

Which kinda rules out the motor.

Now, it is possible the flap arm is not attached to the flap anymore but I would be surprised if that were the case. On the outside it feels solid but who the heck knows what the flap is doing inside before taking the whole bazoonga out to check?!

Back to square one but with much darker outlook.

What the heck else is there?!

I noticed in the manual a "heating resistor" (that's what the manual calls it, see here position 11 http://www.rkoleos.com/images/manuals/133/index408.jpg that is a LHD car, by the way) with multiple connections is part of the heating system. Is that for the blower fan speeds? Or is that a heating element? Would be surprised either way but not that much. I mean the whole thing is so overcomplicated anything is possible.

Anyhoo. I imagine that resistor is only active when the engine is cold not after the engine has warmed up so at some point I should be getting warm air if everything else works. Am I wrong?

Oh, and by the way. If all you need is to take out the flap motor, you can do it after you remove only the piece of trim I pulled out. The screws that bolt the assembly on and the connector are visible or within reach. The screw at the back is hidden but you can find it by feel. A thin socket extension will get you there coming from the brake pedal cutout in the lower dash trim. Turns out the manual is full of shit as we had already established.

I think I might pull out the motor and move the flap control arm by hand with the heater going to see what happens.

Wish me better luck.
 
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Just regarding the "heating resistor" you've queried.
I am guessing this is just the pack of resistors to change the speed of the heater fan motor (may be wrong).
This is often mounted with the actual resistors exposed inside the air duct (to keep the resitors cool).
If you can access that item (item 11 in pic), just undo the screw each end of the plate with the plug on it, and the resistor assembly can be withdrawn - if it is the common setup, which it looks like.

I have also seen (on an older Benz) this incorporated a thermostatically controlled set of points which closed when the resistor temp exceeded safe limits. The switch put the heater blower fan onto high speed to cool the resistors then switched off again. Had one which was incorrectly adjusted, so the car randomly started blowing air from the vents at full speed.

Yes, the vent flap control shafts are a common reason for fault on many vehicles, although the actual number of faults is probably quite low.

Cheers.

By the way, have you changed the cabin air filter? If left too long, the air flow to the vents drops considerably, until sooner or later you get virtually no flow. Usually changed every 30000 kms.
 
i had to do a major head space adjustment when ,when dealing with the flap motor on my 405 Mi16 and SRDT ,its climate control ,flap mixes hot and cold air to give desired temp, on the 405 air is sucked from a slit in the dash ,temp measured then the flap moves through a number of little nylon gears [that strip out ,and are sometimes replaced by gears from a remote control car] ,but i digress, modern cars that have individual controls for driver and passenger ,no drought have two flaps ,and by the way on the 405 the air con had to be turned on to make air colder which in an SRDT tooK the edge of its overtaking and hill climbing ability [you knew when it was on ],and because the air has to be temp tested beforehand, it took a while for anything apparent to happen ,your being a modern car, possibly even more complicated ,its climate control, not a heater .pugs
 
The resistor controls the fan.

Take off the servo motors and look at the end of the flap axles and the motor drives.. PSA flaps I am familiar with are splined to match a metal cog driven by the motor. Being plastic driven by metal, they often strip. PSA heaters are from Valeo, and I suspect many Renault ones are too.

If the shaft is stripped there are solutions mentioned in the Cit forum.
 
seasink said:
The resistor controls the fan.

Take off the servo motors and look at the end of the flap axles and the motor drives.. PSA flaps I am familiar with are splined to match a metal cog driven by the motor. Being plastic driven by metal, they often strip. PSA heaters are from Valeo, and I suspect many Renault ones are too.

If the shaft is stripped there are solutions mentioned in the Cit forum.
Click to expand...

The Koleos is a Korean product...........
 
I know.

But most heater units are similar to the Valeos, and since nobody seems to know much about the Koleos unit, I describe the Valeo one in the hope it will help.
 
Yeah, I thought so too.

The last option that something mechanical is wrong is if the flap arm is not actually attached to the flap any more. Felt solid to the touch but who knows? I'll investigate.

I have some doubts with the resistor being there to control the fan speeds. It is not in the air circulation either. Besides, there are better/easier ways to control DC motors if you already have a jog dial. And why do they call it a "heater resistor"?

Anyhoo, looks to have too many wires attached to it for it to be just a blower fan speed control. Need a wiring diagram.
 
schlitzaugen said:
looks to have too many wires attached to it for it to be just a blower fan speed control. Need a wiring diagram.
Click to expand...
That could mean you do have a resistor ladder but not at the dial, requiring a pair of wires for each resistor step-up.
 
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