Fuel/temp gauge issue

Wes

Wes

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The fuel/temp gauge in my 72 CS seems to be playing up.
'T' light comes on as soon as the car starts - yes there's water in it.
Fuel gauge also reads empty when I know it isn't.
What could be the cause - could it be the temp sensor is broken or a poor connection?
I also pulled the sender unit from the fuel tank and gave it a clean to make sure it wasn't stuck but it hasn't fixed the problem - ideas/help?
 
Both are fuel related, as Andrew said the white "T" is for low fuel in tank, so either your sender is malfunctioning or hooked up incorrectly (maybe your 2 wires are reversed on the sender-3rd is for ground) or the bulb is shorting at the gauge cluster and the gauge wire is not attached. I suspect the sender.
 
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I switched the wires as Steve mentioned before, but never saw a red light. Here's a description from the old tech posts: http://www.e9coupe.com/tech/message051.html
There's also a copy of the owner's manual or "handbook," although it isn't the easiest to navigate: http://www.e9coupe.com/tech/handbook/gallery.htm
(Couldn't bring myself to delete the 9/11 reference)

From : Art Wegweiser <[email protected]>
To : "bart" <[email protected]>, "bmw-coupe" <[email protected]>, "Gary" <[email protected]>
CC : Senior Six Registry <[email protected]>
Subject : Idiot lights, again
Date : Sun, 16 Sep 2001 13:30:18 -0400

Correct - the "L" (red), otherwise called "Batterieladung" reports alternator charging. If on when the engine is running you have an alternator problem, a voltage regular problem, or the drive belt is broken or seriously slipping.

The "O" (orange), otherwise called "Oldruck" indicates low oil pressure. If on, when engine running, shut down at once. It also is alleged to function as a turn indicator for a trailer. (But tow your camper or boat with an SUV.)

The "T" (white), otherwise called "Tanke" is a warning that your fuel is really low. I know of no way to test it other than running the tank down to white knuckle level on a street that has gas stations on every corner. Last (and only) time mine went on I had about 2 gallons. The tank was clean so I didn't suck up any muck.

The "F" (blue), otherwise called "Fernlicht" indicate high beams are on.

The green blinking thing, otherwise called "Blinker" indicates a turn signal is on but doesn't let you know which side (another few pfennig saved in design).

It also blinks when the emergency flashers are on - as does the button below and alongside the steering wheel.

And while we're there, the red light in your tach ("B" for "Bremsen") shows low brake fluid level, or hand brake not fully down, bad float/switch in fluid reservoir or a sticky switch at the handbrake lever.

It is probably wise for us to get back to Coupe and E3 business as much and as soon as possible. All of us everywhere have been deeply touched and will be profoundly affected for a very long time to come.

We especially share in the grief of those whose friends or relatives are gone.
We quietly rejoice for those that have been rescued or that may have come close
but been spared.
We fervently hope that, despite our rage, sorrow and frustration, the dead will be honored by thoughtful and reasoned words and actions. That both ordinary citizens and our leaders, uphold the principles of democracy, honor the most noble traditions of our great Nation and renounce repeating the errors, the shameful and the sometimes evil acts into which we, collectively and individually, have stumbled in the past.
To do otherwise, means the fiends responsible for this have already won.

Art

At 8:10 AM +0200 9/16/01, bart wrote:
The L stands for 'Lager" (not the beer, but the german word that meens capacity or something) and indicates that you have a nasty problem with your alternator not filling up anymore or other elecronical problems...
 
If you ground the wires at the sender unit with the key in on position you should see the fuel tank go to full and the white T light come on. The red L and orange O lights should always be on in this key position until the engine is started.
 
Stevehose said:
If you ground the wires at the sender unit with the key in on position you should see the fuel tank go to full and the white T light come on. The red L and orange O lights should always be on in this key position until the engine is started.
Click to expand...

Thanks, I should have said I never saw a red "T" light. PO disconnected my red "B" light, presumably to kill '74 nanny devices-haven't figured it out, yet.
 
A common problem is with the fuses corroding and not getting good contact.
Try cleaning them and look at arms in fuse box that hold them and make sure they are good.
And the now the disclaimer:
Do not go in the fuse box with a wire brush or something metal without disconnecting the battery.
 
Here are the lights, clockwise

O- Yellow oil
L- Red, alternator and voltage regulator
F- Blue highbeams.
T- White, low fuel
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