Fan not working on 3rd setting and a burning smell

[Vincent.Hamlyn]

For the last 2 months, my A/C hasn't worked on the 3rd fan speed setting. At first, I ignored it. For the last 2 weeks, I have been getting a strong burning smell every time I switch on the blowers or A/C. Are these problems related to one another (ie resistor pack)?

[Dragon]

When my resistor pack died recently I had to pull everything. I noticed that the power wire from the resistor pack to the fan and the #3 setting full 12v power wire were melting the rubber covers on the spade connectors. This could be your problem.

[Iben]

Originally Posted by Vincent.Hamlyn

For the last 2 months, my A/C hasn't worked on the 3rd fan speed setting. At first, I ignored it. For the last 2 weeks, I have been getting a strong burning smell every time I switch on the blowers or A/C. Are these problems related to one another (ie resistor pack)?

Hi There

I had the same problem and had to rebuild the fan control from 2005 spec to 2006 and further.
This it's quite a job but it's doable.

Iben

[ahofste]

Heater fan resistor replacement package (Elise S2) [A120P0148S] - €119.25 : Elise Shop, Performance parts for your Lotus Elise

You may want to consider this. Since my clam is of for some other work anyway, I may just as well upgrade my resistor pack while I'm at it. My car turns out to be from just before the upgrade.

[TheViper]

If I had to do that job, I would seriously consider relocating the resistor pack to a location that is easily accessible from a front access panel, without having to remove the whole HVAC system. These resistors have a habit of not lasting indefinitely, so making it an easy replacement is important, and who wants to go though this process again.
Michael

[dma550]

Is the smell organic or electronic (acrid)? Could be you toasting a mouse nest like I found under my dash.

[Dragon]

Originally Posted by TheViper

If I had to do that job, I would seriously consider relocating the resistor pack to a location that is easily accessible from a front access panel, without having to remove the whole HVAC system. These resistors have a habit of not lasting indefinitely, so making it an easy replacement is important, and who wants to go though this process again.
Michael

I rewired mine up inside the car when I did it, but the resistors run at 240'f according to my IR thermometer. I'm going to have to work on a way to keep them cool so they don't burn up. I'm thinking of using an old CPU heat sink over the 3 of them with the fan, just need time to do it.

[TheViper]

Where inside the car did you mount the unit. I was thinking under an access panel would be a great location. After all, it is only one wire to the blower motor. Resistors of course get very hot.
Michael

Originally Posted by Dragon

I rewired mine up inside the car when I did it, but the resistors run at 240'f according to my IR thermometer. I'm going to have to work on a way to keep them cool so they don't burn up. I'm thinking of using an old CPU heat sink over the 3 of them with the fan, just need time to do it.

[TheViper]

Where inside the car did you mount the unit. I was thinking under an access panel would be a great location. After all, it is only one wire to the blower motor. Resistors by nature get very hot.
Michael

Originally Posted by Dragon

I rewired mine up inside the car when I did it, but the resistors run at 240'f according to my IR thermometer. I'm going to have to work on a way to keep them cool so they don't burn up. I'm thinking of using an old CPU heat sink over the 3 of them with the fan, just need time to do it.

[Dragon]

Originally Posted by TheViper

Where inside the car did you mount the unit. I was thinking under an access panel would be a great location. After all, it is only one wire to the blower motor. Resistors by nature get very hot.
Michael

at the moment I'm only feeding full 12v to the fan and bypassing them until I get time to make something to keep them cool... The biggest issue is trying to feed wires threw the dash on this car since it's stacked in layers of extruded aluminum... I'll definitely be need to drill and rubber grommet some holes and will probably mount it under the center of the dash where I will have good air flow...

[TheViper]

Resistors by nature get hot & although that will eventually lead to their demise, the premature reason seems to be corrosion. Personally, I only ever use "off", or the 3rd speed, so if I had a bad resistor pack I may consider not replacing it.
Michael