Fan Fail and Wobbly Temperature Gauge

[Lotus Jim]

Hello Everyone,
Been wafting about in the Excel today and I have developed three rather annoying electrical problems:
1) Fan fail light comes on as soon as I start the car from cold and then switches off within a minute or so of driving.
2) Temperature gauge will be stable, then wobbles and goes to 40 degrees, then wobbles and sits back to the running temperature. (This one has actually been going on for a few months )
3) Interior lights stopped working. Replaced the fuse and it went pop immediately, so I just put the panel back on and hid!

So what do you chaps think could be going on? I'm not going to drive the car until I have sussed the fan fail and temperature gauge wobblyness out.

Jim

[amarshall]

For 1 - it's meant to come on and go out after about 10 seconds. Since it also indicates low coolant, check the level in the header tank.

2 & 3 may be related - possibly a bad earth somewhere.

2 may also indicate insufficient coolant or a failing sender.

For 3 - check bulbs and switches.

[Lotus Jim]

Thanks for that Angus, thats ace.
I'll check the coolant first, then following that I might start checking earths and things.
Jim

[amarshall]

Just a thought - when the temp. Gauge reading is wrong, check the other gauges. If one of them is also "off" then it will be an earth problem.

[Lotus Jim]

I'll double check, but I think all of the other gauges are OK when the temperature gauge drops out. Does that sound like low coolant / sender?

[royal]

For the interior lights check the wiring from the body into the doors, I've just had this problem and the wires were breaking and shorting out the fuse, my car is earlier than yours so that fuse also covered the clock memory, radio memory and the door warning lights, hope that helps

Keith

[Lotus Jim]

Hello Keith,
Thanks for that mate. I think that is probably the cause as the light on the end of the drivers door has packed up. Looks like I need to spend some time with a multi-meter!

[Lotus Jim]

Hello Chaps,
Checked the water level when cold, both sensors in the expansion tank were above the water line by a fair margin. Topped the tank up to the point defined in the manual and the light hasn't come back on and the gauge wobbles during warm up and is stable when warm. Will take the car out for a longer jaunt over the next few days, but hopefully thats cured the fan fail and gauge wobble issues.
Next up...that pesky door loom!
Jim

[Lotus Jim]

Found the problem with the wobbly temp gauge. The connector on the temperature sensor was in a bit of a sorry state and was a bit "smegged" up. Refetteled it and all is fine!

Jim