Does anybody's low fuel light work on their C3? If so, when does it light?
I have driven the car for about 25 miles, after the gauge says empty but the light does not go on. What fuse controls this fuction? I know its not the bulb, because I replaced all of them when the dash was out.

By the way, the car is a '77.

Thanks
Larry :seeya

 

Mine came on once. It started dim and got brighter, especially when I accelerated or turned a corner.
I had been on or really close to "E" for a while and was desperately searching for a gas station.

 

Yes...of course! The 77 is identical to the 78 and was actually the forerunner for the 78's new one piece dash. Mine comes on often since my fuel tank sending unit is going.

Did you touch the bulbs with fingers when you replaced? Not that that would compromise their functionality but it does affect their life span.

Like you...I like to drive once needle gets to E to determine at what point the light comes on. The 78 has 24 gallon tank and I believe I've estimated that their are about 4 gallons left when the needle hits E. The light doesn't come on until about two gallons out!

My light will come and fade at steady driving. Once I've traveled for a distance...it will come on permanently. I can still drive another 30 miles or so and while I've never tested it...there's still gas left in the tank. At approximately 18 mpg, that means if I'm running around 30 miles...I've run the tank down to about 2 gallons. It's pretty much running on fumes at this point.

So, bottom line is if you run til light comes on...your fuel gauge needle will have passed the E on the gauge and you have at least two gallons if not closer to four in a 77 which sports the 18-20 gallon tank.

From what you describe...you may have to push it another fifteen miles (3 gallons) to get the light on. Good luck and let us know what you learn

 

mine used to work fine then it stopped working...
on mine the problem was the little circut board on the back of the bulb...
i took it to a freind at a TV repair place and he inspected the board with his magnifying glasses and determained that some of the soldered connections had become loose with time...
he resoldered them and tested the capacitors etc and they were all fine...
no charge! tipped him $5 (took him 15 minutes while i waited)
works fine now! :yesnod:

 

Mine works fine but as everyone points out, it is well below E before it comes on. Get your self a 2 gallon gas can and drive it until the light comes on. If it doesn't put your 2 gallons of gas in the tank and head to the next gas station.

Bob

 

Touching the bulb only applies to halogen bulbs (like H4's). You can finger a normal incandescent bulb (like a taillight or dash bulb) all day and it won't affect it... :smash:

 

Mine worked with the 355,but be damned if I didn't run out of gas on the first tank I ran with the 406. :mad

 

I agree with the 2 gallon rule for the light to come on steady. Just don't be too far from a gas station when it does. Having some gas in a can with you is probably a good idea if you really want to test the light without worrying about getting stranded.

 

Mine stayed on all the time after replacing the bulb, so I took the dash back apart and pulled the bulb out. I hate running a tank down on any car so I really didn't have a need for it.

Colin


[Modified by Colin, 12:53 PM 11/30/2002]

 

Does anybody's low fuel light work on their C3? :smash:

Does my '76 even HAVE one??

 

Mine does not. I found out the hard way :D

 

I saw mine come on once, only about 2 gallons left in the tank. I never run it that low any more. :cheers:

 

I have never seen one on my 75. :eek:

 

my 79 does but never seen it light up...then agian the gauge is a little whacked too...it never drops below a 1/4 of a tank... I think i have either a ground issue or a sending unit issue...

 

well since it's been dead and revived..

This Video should help test your module before you put it back in the car.
And just a warning.. there is a schematic that has floated around the forums on the low fuel modules that is not correct....





Willcox

 

I was just going to say (as I was reading this REEEEALY old thread...) that Willcox has an article on testing the circuit board.

I have never run mine that far down, so I don't know if mine works or not. Good idea with the extra gas can.

Jim

 

The easiest way I've found to test the LOW LIGHT function is to ground the sensor wire coming from the fuel sender (the pink wire on my '81) and count to 30. If the light works, it should come on in 20-30 seconds. Your fuel gauge should drive to empty when you do this.

 

Hate bumping an old thread... but the correct repro of this module will be finished in a few weeks.

 

Now that you've raised an old thread...any pics? Where's it mount? This is so old I've now forgotten?

 

My low fuel light came on once and it gave me about a two mile notice before I ran out of gas. Fortunately I was in my driveway.