Probably the blower resistor pack, especially if condensation got it

 

Is this the item that controls the fan speed? Is there a fuse I can pull to stop power going there to avoid a fire?

 

fan is on the left side of the car, it is right in front of your feet

Since the fan worked[and brought smoke into the car] I doubt this is it

Things in that front corner
Relay pack, fusebox, oil cooler, radiator hose

 

The fan wiring carries all 20A throughout the full circuit (no relays), so anywhere those wires run can get hot when the resistor pack shorts from moisture. In my experience, some dust behind the speed control knob caught fire once in the rain because of all of this years before the pack actually died. I yanked the console out and blew out the flames, put it back, and kept driving. My wife wasn't quite as calm and asked why I didn't pull over, and I said "well, the fire is gone now" haha. Whatever flammable dust there was back there burned off, and we finished the drive without any other issues.

 

Yes the fan does work. Does that rule out the fan resistor pack or is is possible it got really hot and starting melting plastic?

There is no coolant leaking and I did replace the radiator with aftermarket a few years ago. There is also no oil leaking. It definitely smelt of burning plastic. I looked the fusebox on the right had side and nothing appears to be burnt.

 

Sometimes the resistors die and only the low speeds are affected, sometimes it doesn't work at all. Mine were dead when I got the car so I never saw smoke, I don't think that is common

Enough smoke from an electrical source ought to pop a fuse, which gets us to the fusebox again

Check wheel liner rubbing on the tire or something?

 

Yeah, fair enough

In my going through the HVAC, I ended up putting a relay and connection to the nearby battery posts on the Exige because it gave measurably more air flow compared to connecting through the switch and skinny wires

 

Yeah, that’s definitely on my to-do list and why I am so skeptical of the whole circuit

 

Fan was not running prior to noticing smoke. I turned it high and heat thinking the car might be overheating. Is the fan resistor pack receiving power even when the fan is not on? (ie. could it be melting from corrosion or shorting and creating heat). If it's not the resistor pack, I don't know what else could have melted that is a known issue. I don't know what else to check as anything I can view by removing the access panel looks fine. What is under the plastic panel that the fuse box screws too?

I am thinking it's something in the HVAC system only because turning the fan on immediately starting pushing the smoke through the vents. I haven't started to the car since then as want to avoid a potential fire or at least mitigate that risk if it's the HVAC system and pull the 20 amp fuse. Any ideas on steps to take?

The closest Lotus dealership is 15 hours away and I have taken the clam off before but never dealt with the HVAC system other than the upgrade thermostat

Thanks for all the advice. It is very much appreciated!

 

No, no power to the fan circuit when it is off unless you have a short somewhere, in which case the fan would not likely run when you told it to. Given the tie-in the air ducting, could it have been a headlight heat sink and the smoke just got drawn in through the radiator ducting? If the lights were off, this would be a long shot at best.

 

In Canada headlights are always on but I have the ducts in the grill taped off so I don't know smoke would have been pulled in. I took the access panels off and will run it later and see if something starts to smoke to narrow the issue. If no power to the fan circuit when off, then I guess it's not likely the fan resistor pack.

 

Hmm, I was hoping you didn’t have them taped off (for this purpose). The only intentional way for smoke to get in then is from cabin, right @exigegus ? Makes me think the corrugated hose that goes from the heat/AC box to the cabin has come loose and could be drawing the smoke in, so that’s about where I’d check next.

 

The unmodified hvac system is pretty leaky
Something in the nose would get sucked right into the fan

 

I doubt this is your problem...one time my dealer installed a heat shield and left the Lotus OEM sticker on it. The sticker started to melt and it smelt terrible. Have you installed any parts recently?

 

Nothing new installed. It was however the hottest day we have had in a very long time. It was +42C with the humidity. The car wasn't overheating though so I am hoping something "not important" melted from the heat but I was thinking maybe the resistor pack shorted and melted as that is an known issue but the fan was off when the smoke started. It was on earlier than that though.

 

I think the peace of mind with a clam removal to check R pack and all wiring speaks volumes!

 

So I found fuse # 7 blown. This is labelled as 10 AMP fuse and ignition services. Does anyone know everything that is on this fuse so I can do some more exploring?

Thanks to the Lotus fam for all the help!

 

From the wiring diagram, I found these:

Starter button
Cluster
Alarm
Mode actuator
AC relay
Temp actuator
Recirc actuator

Those last four are the closest to the ducting, but none of those were activated, right? Or were you running the interior fan just without AC?

 

I did have the AC on as it was a hot day but it needs to be recharged so it does't work very well. I believe it was off at the time and the fan when I first saw smoke and then I turned the fan on high (on heat) because I thought the car may be overheating.

The last four all involve the AC right? What does the mode actuator and temp actuator do and I can confirm whether they are working or not.

There definitely is a burning plastic smell coming out of the vents but no smoke anymore. Based on that fuse being blown, I would suspect that something in the last 4 items drew a lot of current, melted something and tripped the fuse.

After replacing the fuse, the cluster (GARW) now lights up and alarm works. The starter button never stopped working which is odd right?

I started the car and let it run for 20 mins in the driveway and no smoke and fuse didn't blow again. I also confirmed the fan works on all 3 speeds.

I saw on another search that someone believed the daytime running lights (in Canada here) may be on the same fuse too.

Getting closer to an answer so thanks for all the help!

 

In post #12, you said the fan was off which means AC was off. Then you say you were running AC because it was hot, and the next sentence says it was off. So… which is it? If the fan was actually running, I’m back to thinking it was the resistor pack or related wiring.

Those actuators are various flaps for controlling the blend of heat/AC and where it is directed. With an ear near the heat/AC box, you should be able to hear them move when someone changes the knobs in the cockpit. I’ve had two fail, but they are pretty lightweight and low current. Since that fuse goes to your aftermarket dash, too, it’s possible it is a second issue.

 

The three actuators listed are all front right of the car, outside.

 

So now that I understand how this fuse works I can maybe understand how the fuse blew. I had been driving around on a hot afternoon and had the A/C on. About 15 mins before the smoke and fuse blowing, I am pretty sure I turned the AC off as it was just blowing hot air. I stopped at a light and saw some smoke coming up from the clam. I thought, given how hot it was that the car was maybe overheating. I remember looking down at the GARW dash and seeing the temps were not in the red but I thought maybe something is wrong with it and I turned the heater on hot. When I did this, smoke came through the vents and the GARW dash display turned off (which makes sense now that I know it was on that fuse).

I left the car sit for 30 mins and then drove home and there was no more smoke (but fuse had blown). That tells me it's likely something on that fuse and since smoke was coming through the vents, likely something close to the A/C system. I have since replaced the fuse and starting testing starting with letting the car run for 30 mins yesterday in the driveway with no issue. The next step will to try the actuators and see if any stopped working. Fan speeds all work so I am assuming resistor pack is still good and the fuse for the HVAC fans did not blow.

 

So you can check if the vent/defrost/floor actuator works.
once the car is warm you can see if the hot cold actuator works
the recirc actuator is harder, but you might be able to lay a hand on it

 

You can hear them all move, so you shouldn’t even have to have a visual as long as you lean in close while someone moves the knobs. I believe the AC relay that’s also on that circuit is near the front fuse box, so you should also hear that click. Check it for signs of burning, too.

 

All the actuators work. I pulled the AC relay plug off and discovered that two of the relay pins and the harness have melted. Does anyone know how hard it is to replace that harnes or should I just try a new relay first?

 

 

Anyone know where to get this relay? I tried the part # on ebay and it comes up from other vehicle. Are they all the same?

 

Is this what you're looking for? Lotus OEM Fan Control Module (Multi Relay) - Elise Exige 2-eleven 2005-12

There was a SB out on it for cutting engine power in the '06 Exige S - Engine Cutout A/C Relay information

 

Yes. I see the same part # on eBay for rovers for a lot less. Would it be interchangeable on the Lotus?