All interior illumination gone

[garymb]

Having same problem as elan man: "...all my panel lamps/illumination have all gone off, when I mean the panel illumination I mean everything like speedo, rev counter, boost gauge, oil pressure, volt meter, temperature gauge and fuel gauge."

I checked he interior lights fuse (ok) and replaced the rheostat but still no interior lights (exactly as elan man). any ideas anyone?

[Gary]

Open the binacle over the dash and twiddle all the connectors.

The other things that might work (don't know why, but did for me), is to put the interior lights on and then off again

[Doug]

I'd say you have checked the right things so far.

you need to get the circuit diagram for the interior lights and troubleshoot it

for example check the lines with a voltmeter and jump 12V to parts of it as needed to see where the problem is

definitely check the ground to the circuit too!!

[garymb]

Thanks guys, will try all these things-- if they dont work out I guess it might be the rheostat module.

[Doug]

if they dont work out I guess it might be the rheostat module.

well, Rheostat is my definite number one suspect, but you said you had replaced the rheostat??? you should definitely check its contacts and resistance values to be sure it is working right !!

[GeoffSmith]

The rheostat module (rather than the rheostat, twiddly thing with a knob on the dash) takes the voltage set by the rheostat and puts that voltage on all the lights. Without either working correctly, the lights won't work.

[Doug]

well, fu@% me ! I thought they were one in the same

[GeoffSmith]

Nope - it's all electronical these days!

[garymb]

Turned out it was this (or the lack of one!) It was simply missing in this car (bought from UK sports cars, Kent).

Got a replacement in the Lotus parts sale for £7.20 fortunately as opposed to the normal £120 or so. Everything works fine now.

[GeoffSmith]

[Gary]

Got the same problem. Tried everything. Lights under mirror work so guess it isn't the fuse ???

How do I know if the rhoestat has gone, and how do I get it out ?

[garymb]

I got this from the ever helpful there's only on f in Geof Smith (attached). My rheostat module turned out to be missing completely! When you locate it (you need to get your head down by the pedals and look behind the fascia-- it is one of the larger modules. In my case the replacement module was green, not sure if the original ones were).

I think you have to zero-in on the module as being the problem by a preocess of elimination, fuses rheostat/potentiometer (the dimmer control itself) etc. If it is the module you are in luck as they are in the Lotus parts sale A100M6059F for £7.20 (originally they were £120!) Worth buying one to see if it fixes the problem-- as it's bound to go at some point if it's not the issue right now!

[Gary]

oh, so it is just that box unit then, I presumed it would be the actual switch on the dash that was the problem. I'll have a look at the weekend. Thanks for that

[Gary]

Call me stupid, but I had a look and couldn't find this.

So is this the block under the cowel above the steering wheel ? No underneath it ??

[GeoffSmith]

When you locate it (you need to get your head down by the pedals and look behind the fascia-- it is one of the larger modules.

Here's a hint Gary!

[Gary]

So it is above the peddles, driver side then? Didn't have much space as couldn't get the car out the garage today 'cos of the rain...

[GeoffSmith]

Stuck a mirror down there! I just have and they are mounted just in front of your right knee, right at the bottom. If your hand-eye coordination is good, I reckon you could change it in about 10 seconds with a mirror.

[Gary]

I'll have a go next weekend.

I'm not used to putting a mirror down there, isn't that what women are supposed to do ?

[Gary]

Right, I've tackled this job today. You diffenetly do need a mirror, and the light module is green.

Being luckier than most I was able to swap the module out of one car into the other and yep that fixed it.

So now just need to order a new module from the parts sale