Coolant warning light

[xavier]

My coolant level warning light won't go out. There is plenty of coolant and I swapped in a spare sender/water level float device thingy. The engine running temperature is perfect even though the weather was 39 degrees celcius yesterday when I was driving. even with the lead to the sender removed the light stays on. I am pretty sure it is a short. My son followed the wire all the way back to the warning light panel on the roof of the car, but he could find no short. Even with the wire disconnected from the warning light panel the light stays on. Any suggestions?

[Brianmoooore]

Light stays 'off' when there is a short. Pull the plug off of the sensor, use a wire link to short the pins of the plug together, and then turn the ignition on. If the light stays off, then the sensor is the problem.
If this appears to be the case, you may have fitted the wrong sensor - check that the light doesn't go out when the bottle is empty.
If the light still remains on with the link in place, the most common problem is a broken wire internally, right where it goes into the plug.

[xavier]

OK ta. I will pick up another sensor tomorrow and see what happens.

[pianist]

Or just try shorting it with a wire like Brian said lol

[Brianmoooore]

Don't 'pick up' anything until you have tested. Random changing of parts without testing is the best way to get yourself into an unsolvable mess when repairing cars (and most other things).

[xavier]

Thanks Mr Moore. I fitted a new sender and all is working well. A learning experience. Now to find out why the indicators don't work.

[Brianmoooore]

Now to find out why the indicators don't work.

Usually the hazard light switch. Not used for years, then someone tries it, and dirty contacts inside prevent the 'normal' power for them being reconnected when the hazards are turned off.
Easy to strip, clean and reassemble.

[xavier]

Ok. If it is the hazard light switch, will the hazard lights still work if the one of the indicators wont? The left hand indicator works all the time, the right hand indicator only works when it is in the mood. The Hazard lights are still happy to work on my old car.

[Brianmoooore]

You said they didn't work. Now you say they don't work properly, which is a completely different thing!
If the RH indicator only works occasionally, then it's probably the indicator switch. If it works at the wrong speed, then it's probably a poor connection somewhere, possibly in the bulb holder.

[xavier]

OK sorry for my poor description. You mentioned in an earlier post not to replace parts at random, if there is a chance that it is the indicator switch, should I try swapping in a spare second hand one that I have? The local BMW dealer quoted me $600.00 for a new one, but fortunately I have one pulled from a car being wrecked.

[Brianmoooore]

Again, test first. Find the plug/socket for the indicator switch, half way down the steering column, and use a short wire link to connect together the green/yellow and blue/black wires. Turn the ignition on and the RH indicators should be working. If they're not, then it isn't the switch.
Green/yellow to blue/red works the LH indicators.

[xavier]

The right hand indicators work when I perform the short you suggest. When the wires are removed the Right hand side indicators stop. So this suggests it is the switch. Shall I try my spare switch? Also there appears to be a black and yellow wire that runs to the flasher box input but there is no prong on the flasher box that fits into it. I cannot find mention of it in my manual. Any idea what it does?

[Brianmoooore]

If the flasher module socket has four wires, then it is probably wired for a trailer warning light.
This light is immediately to the left of the service indicator LED panel.
Four pin flasher modules with the trailer warning output are available as a direct replacement for the three pin version, and are fitted to a few of my E30s.

Change the switch for your spare one.

[xavier]

Thanks Brianmooooore.

[xavier]

All indicators working. Thanks Brian Moooore