Burning plastic smoke from heater vents! Uh Oh

[Billy Smalls]

Hi - it's shame when one of the first posts you write is after advice for a problem.

So - heat on full, fan on 3, sat in traffic so try out the recirculation button (first time trying it), smell of burning plastic, kids not happy, try switching off recirculation but light stays on, pull over when youngest points out acrid smoke coming from centre vents.

switch blower to zero - blower stays on?! - have to pull the 20A fuse to stop the blower working and get home unfried

dark out there now - so will inspect in the morning but anyone had this issue?

Cheers all

 

[Crybert]

The car would help

 

[Billy Smalls]

Sorry, yes - this is a Clio DCi 2003 with air con (though I wasn't using that) thanks

 

[MRBILLYUK]

Sounds to me like it could be the heater resistor pack knackered and over heating. It controls the speed of the fan. They can get very hot. Vauxhall had a problem with theirs over heating and the cars setting on fire.
If it's in the same place as a 182 it's under the drivers side scuttle.
If you have a search on here you'll find more info.
If it's not a separate resistor like a 182 it'll be integrated in the blower motor so you'll need to replace it all.

 

[Louis]

I'd reiterate the above too. Easily checked by disconnecting the resistor pack then reconnecting the fuse. It could also be the wiring or the heater motor itself.

You just need an 8mm socket/spanner to get to the resistor iirc.

 

[MRBILLYUK]

Thinking about it now. I'll bet yours has the resistor integrated on the motor.
I had a burning plastic smell last year when the fan was on. It turned out the fan was knackered.
I sourced a 2nd hand one from a breakers but it had the resistor built onto a board next to the fan.
I just bypassed it and it works with the original resistor pack.
It's a piece of piss to change the fan.
Have a look at post #6
https://cliosport.net/threads/guide...wer-motor-from-clio-mk2.834181/#post-11962197

 

[Louis]

I'm not sure you know. Easily checked over by OP! How are your spannering skills @Billy Smalls ? Obviously not ideal into winter having no fans.

 

[Billy Smalls]

Hi Mr. Billy & Louis - great that gives me a good start. I'm not bad with spanners - I'll take a look tomorrow

It seems weird that the air re-circulator light stayed on and the fan didn't switch off with the knob.....maybe heat has created a circuit due to something melting??

 

[Louis]

Hi Mr. Billy & Louis - great that gives me a good start. I'm not bad with spanners - I'll take a look tomorrow

It seems weird that the air re-circulator light stayed on and the fan didn't switch off with the knob.....maybe heat has created a circuit due to something melting??

I'd not realised it was the original climate panel with the dials. It is a bit odd that it stayed on, but if the resistor is having a fit it may be giving odd signals back. Believe the recirculation panel just relies on the motors behind moving the cogs.

It could be one of these has failed along with the CC panel itself. This would make sense as it's not that it instantly went onto full power you just couldnt turn it off once it was there.

A few avenues to explore I guess! You can remove the panel relatively easily and disconnect it and see if that solves your issue too.

 

[Billy Smalls]

I managed to get the dial panel off with lots of broken brittle plastic as expected (sorry for cynicism) - rheostat plastic lugs snapped in seconds - so it's not pretty.

Anyway - put the fuse back in, turned the ignition on and sparks / flame size of a cigarette lighter in the loom from the PCB - just where it sits adjacent to a big steel bar that runs vertically behind the dash, just by the driver's left leg.

managed to blow the flame out!!

I'm wondering if a hot wire has melted it's plastic shielding and is shorting out on the metal bar?

Weird that the fuse allowed this to happen???

I should point out that whilst I think Clio's a good cars - this is a beater / A2B car - just disappointed that my chamois leather is going to be doing the job on cold mornings and I'll need to wear 2 pairs of socks!!!

 

[Billy Smalls]

Thinking about it now. I'll bet yours has the resistor integrated on the motor.
I had a burning plastic smell last year when the fan was on. It turned out the fan was knackered.
I sourced a 2nd hand one from a breakers but it had the resistor built onto a board next to the fan.
I just bypassed it and it works with the original resistor pack.
It's a piece of piss to change the fan.
Have a look at post #6
https://cliosport.net/threads/guide-needed-for-removing-heater-blower-motor-from-clio-mk2.834181/#post-1

Hi - I now have the fan out. the resistor is very rusty but doesn't appear burnt. if I spin the fan with my hand once it only turns 3 or 4 times - should it spin for much longer?

I'd like to test the resistor and fan before spending money on new ones - the fan is showing a resistance of 0.8 Ohms - does that sound correct?

My main problem is I have a 15 wire loom, with all but 3 wires melted / fused together behind the dash!!!

What a mess! My car is MOT worthy right now - but no de-mister in this weather is not fun

 

[R3k1355]

Rain-Ex the inside of the windows, solves your misting problem anyway.

You've always got the option to slam it back together, chuck a key in the ignition and let it burn itself to the ground.

 

[Billy Smalls]

Rain-Ex the inside of the windows, solves your misting problem anyway.

You've always got the option to slam it back together, chuck a key in the ignition and let it burn itself to the ground.

I could but I kind of need the car!! ha ha

 

[MRBILLYUK]

Hi - I now have the fan out. the resistor is very rusty but doesn't appear burnt. if I spin the fan with my hand once it only turns 3 or 4 times - should it spin for much longer?

I'd like to test the resistor and fan before spending money on new ones - the fan is showing a resistance of 0.8 Ohms - does that sound correct?

My main problem is I have a 15 wire loom, with all but 3 wires melted / fused together behind the dash!!!

What a mess! My car is MOT worthy right now - but no de-mister in this weather is not fun

I couldn't tell you how many times it should spin by hand but with mine you could feel when it was spinning it felt rough. It definitely didn't spin 3 or 4 times.

 

[Billy Smalls]

All sorted now - the loom melted loom was so hard to get to I just isolated each of the 15 wires, set up a switched relay straight from the battery and the cold and misty windscreen is sorted.....dash is a bit of a mess mind you