And the latest spanner in the monkey is

schlitzaugen

1000+ Posts
Yeah, I know but why would anyone bother with all this resistor crap when you can have a PWM control since you have a digital control interface already?

I'm not saying it's impossible the resistor is in fact for the speed control but if it is, boy is it ever so the century before last! I mean we splash out on LCD displays everywhere like there's no tomorrow, computers everywhere even the flippin' lights are multiplexed and we still use a friggin' resistor to control a stupid DC motor?!
 

simca1100

Member
OK let's answer some of Schlitz's questions from the original post:
(From someone who has never even sat in a Koleos, but fixed a similar problem in a friend's Pug 307.)
the two dials will be left/right, NOT front/back.
One heater matrix.
It is an air-blending heater. This means heat is NOT adjusted by varying the flow of hot water, like it used to be on old Renaults and many other cars. It has one heater matrix that always runs hot. It has a second airflow that brings in unheated air (air conditioned if aircon is on and temperatures require it.) The temperature adjustment is achieved by blending the hot air supply with the cold air supply to achieve the set temperature.
Modern cars generally have two sets of mixing flaps, one for drivers side and one for passenger side. Each has its own temp dial.
It is VERY common in Peugeots and Citroens of a certain age to have a plastic gear strip in one of the mixing flaps, so that the flap does not respond to the movement of the adjusting motor. The problem was fixed in 2006 or 2007 build cars, with stronger components. My 07 car had no problems, my friend's 05 or 06 car had the issue on one side.
Peugeot came up with an ingenious solution so you don't have to dismantle the whole fu**ing thing to swap a simple flap. A new cog is engineered to fit over the old stripped cog, no need to remove the old stripped plastic cog. Then a new spacer is added to move the motor out enough that the motor engages with the new cog.
It is a clever fix to a silly basic problem.

I hope that either Renault uses the same heater box as Pug (if it's from Valeo it is a possibility), or that Renault has a similar solution for your car.

about resistors - I don't think a heater fan resistor is the issue here. There is often also a resistor in series with the small DC motors that operate the flaps. It is a pretty crummy design, the motor doesn't stop being fed power when it gets to the end of its travel, there is no limit switch to cut power when the motor can't turn any further. When the motor has moved the gears as far as it can, it just stalls and the resistor dissipates, as a small amount of waste heat, the current drawn by the stalled motor. If the resistor fails, the motor doesn't turn, flap stays where it is despite you adjusting the dial. Find and replace dud resistor, heater flap moves again.

As stated above, this is based on a 307 I played with over 10 years ago, plus a little I have read (the resistor stuff.)
I dunno if any of it applies to a Koleos, but it's an idea for you to investigate.
 

schlitzaugen

1000+ Posts
Thank you very muchly indeedly.

I seem to be cursed to have to work under the dash of my cars. I can't remember one that didn't pull that dirty trick on me. I am pretty sure I spent less time doing everything else put together than working under the flipping dash.

You can understand why I like it so much.

I guess that's the main problem.

I think we kinda blundered our way (mainly) towards the truth in the end. Thank you for the extra info.

My flaps don't sound like there's any broken gears. Both motors and flap levers move smoothly and through their entire travel (by that I mean there's no obvious difference between the travel on the left, which I know is good and the right).

I suspect it's more likely to be one of those connectors that go through the heater control board (no idea what that does) like the explanation in the post I linked earlier from another forum in the UK. Just in the interest of making sure this horse is buried alive I will however physically check the flaps (because now I know how to get to them and it's easy) but don't hold much hope it'll be them.

Can't promise I will go back in there soon, but I can promise there will be profanity involved when I do.

Keep your antisocial distance.
 

schlitzaugen

1000+ Posts
I bought a manual with wiring diagrams, they're about as useless as the manual everybody has found on the 'nets. In fact it is the same manual. All the info everybody seems to find on these cars seems to be the same info, based on the same (almost) useless manual.
 

505604

Member
OK let's answer some of Schlitz's questions from the original post:
(From someone who has never even sat in a Koleos, but fixed a similar problem in a friend's Pug 307.)
the two dials will be left/right, NOT front/back.
One heater matrix.
It is an air-blending heater. This means heat is NOT adjusted by varying the flow of hot water, like it used to be on old Renaults and many other cars. It has one heater matrix that always runs hot. It has a second airflow that brings in unheated air (air conditioned if aircon is on and temperatures require it.) The temperature adjustment is achieved by blending the hot air supply with the cold air supply to achieve the set temperature.
Modern cars generally have two sets of mixing flaps, one for drivers side and one for passenger side. Each has its own temp dial.
It is VERY common in Peugeots and Citroens of a certain age to have a plastic gear strip in one of the mixing flaps, so that the flap does not respond to the movement of the adjusting motor. The problem was fixed in 2006 or 2007 build cars, with stronger components. My 07 car had no problems, my friend's 05 or 06 car had the issue on one side.
Peugeot came up with an ingenious solution so you don't have to dismantle the whole fu**ing thing to swap a simple flap. A new cog is engineered to fit over the old stripped cog, no need to remove the old stripped plastic cog. Then a new spacer is added to move the motor out enough that the motor engages with the new cog.
It is a clever fix to a silly basic problem.
~ snip ~

As stated above, this is based on a 307 I played with over 10 years ago, plus a little I have read (the resistor stuff.)
Thanks for that explanation of how the heating/cool system works. I had been told some of that a few years ago but I didn’t remember much of it.

But I really want to thank you for the video link. He has lots of useful videos on YouTube. I can see myself spending a lot of time on his channel!

Cheers,
Andrew
 

schlitzaugen

1000+ Posts
OK let's answer some of Schlitz's questions from the original post:
(From someone who has never even sat in a Koleos, but fixed a similar problem in a friend's Pug 307.)
the two dials will be left/right, NOT front/back.
One heater matrix.
It is an air-blending heater. This means heat is NOT adjusted by varying the flow of hot water, like it used to be on old Renaults and many other cars. It has one heater matrix that always runs hot. It has a second airflow that brings in unheated air (air conditioned if aircon is on and temperatures require it.) The temperature adjustment is achieved by blending the hot air supply with the cold air supply to achieve the set temperature.
Modern cars generally have two sets of mixing flaps, one for drivers side and one for passenger side. Each has its own temp dial.
It is VERY common in Peugeots and Citroens of a certain age to have a plastic gear strip in one of the mixing flaps, so that the flap does not respond to the movement of the adjusting motor. The problem was fixed in 2006 or 2007 build cars, with stronger components. My 07 car had no problems, my friend's 05 or 06 car had the issue on one side.
Peugeot came up with an ingenious solution so you don't have to dismantle the whole fu**ing thing to swap a simple flap. A new cog is engineered to fit over the old stripped cog, no need to remove the old stripped plastic cog. Then a new spacer is added to move the motor out enough that the motor engages with the new cog.
It is a clever fix to a silly basic problem.

I hope that either Renault uses the same heater box as Pug (if it's from Valeo it is a possibility), or that Renault has a similar solution for your car.

about resistors - I don't think a heater fan resistor is the issue here. There is often also a resistor in series with the small DC motors that operate the flaps. It is a pretty crummy design, the motor doesn't stop being fed power when it gets to the end of its travel, there is no limit switch to cut power when the motor can't turn any further. When the motor has moved the gears as far as it can, it just stalls and the resistor dissipates, as a small amount of waste heat, the current drawn by the stalled motor. If the resistor fails, the motor doesn't turn, flap stays where it is despite you adjusting the dial. Find and replace dud resistor, heater flap moves again.

As stated above, this is based on a 307 I played with over 10 years ago, plus a little I have read (the resistor stuff.)
I dunno if any of it applies to a Koleos, but it's an idea for you to investigate.

That video mentions the "auxiliary heating resistor", which I take it, means it does some actual heating (perhaps before the engine heat works its way up the pipes to the heater core). Which if true, throws another monkey at me.

As I mentioned before, the temperature of the air coming out of the driver side vents does get lukewarm eventually but by then the passenger side is quite toasty.

And the motors themselves kinda look like that (I think they have three screws) but they control the flap with a push-pull lever not a cog. At least on the driver side. Mine moves about seemingly correctly but that doesn't preclude the possibility the flap lever arm is somehow detached from the flap itself. Or somehow disengaged or something.
 
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