warning lite in the dash...wont go out..but my lite bulbs are ok..parking turn, hi/lo, rev, brake

1987 765ti

so this little thing wont go out........

the warning bulb that says you have a lite out.....I don't....but the bulb will not turn off....wanring bulb that is...

now, the lite bulb comes on when I turn on the parking lites...and it stays on....

what could be wrong?

take out all bulbs, and dielectric grease all contacts? fix rear licencs plate lites? drop back 10 yards and punt? the console, ashtray front and back, and the glove box don't work...but I don't think it would be that....

any one else have this problem?

any ideas?

thanks

Reply to
surfbug
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A very common problem. Any imbalance within a pair of bulbs (front pair or back pair) will cause the light to come on. You can determine whether it is the front or back bulbs doing this by removing either the parking light bulbs *or* the tail light bulbs and see if the symptom goes away. If it goes away, replace both of those bulbs with a brand new pair. If not, leave those out and remove the other pair. Now if the symptom goes away try putting the first pair back in. If all is okay with the first pair back in, replace the second pair with a brand new pair. If the symptom never goes away or if it returns when you put the first pair back in, remove the "bulb out" detector and resolder the connections inside or replace it with one from a wrecking yard.

If the problem is isolated to the parking lights or the tail lights and replacement doesn't help, carefully work over the contacts and grounds for those bulbs.

Mike

Reply to
Michael Pardee

roger that!

I am gonna check this out,,,,,,hop eit works.....

thanks!

al

Michael Pardee wrote:

Reply to
surfbug

Alternate solution is the lazy one: don't worry about it but do a regular walkaround and check the lights.

The perfect time to do this is when you do your regular weekly checks on fluid levels and tire pressures.

Oops! Let me guess. You don't have that regular weekly habit -- don't worry, most drivers don't but should. Me too! I'll admit that ($-

Reply to
byrocat

Still difficult to check the brake lights, unless you have something shiny behind you.

Reply to
James Sweet

Brake lights work with the engine off so you can test them in the garage with the door down.

Reply to
Alotta Fagina

Reply to
Inno

Check the fuses! Same thing happened to me in my 1990 240, and all the lights were fine, but 2 fuses were blown. Didn't figure it out for 2 months (I hardly drive), took 3 seconds to fix!

loren

Perry Noid wrote:

Reply to
lolo

I've had so many "lite-out alerts" over the years that I carry a wooden stick that I can wedge between the front edge of the driver seat and the brake pedal, to hold it down. Then I walk back and see which brake light is out. Unfortunately, I recently noticed that when I lift the tailgate ('89

240 wagon), the center brake light flickers or goes out, so I'm guessing I'll have to replace the flexible cables into the tailgate sometime soon... any suggestions?
Reply to
Perry Noid

I recently replaced a headlight on my '83 245 with one I had kicking around the garage. The lamps in it are generic sealed beam (sealed... lol, I had to replace the one that was ¼ full of water.) The one I put in was one of those expensive "quartz" lamps. The warning light still comes on when I turn on the headlights. Both lamps work. S'pose having a quartz one on one side and a clunky old sealed beam on the other can cause this too?

Reply to
clay

That would do it because the light out unit works on detecting the current on the left and right sides are equal. If they are unequal it will trip the alarm. Different bulbs can draw different currents. If you have a nervous light out unit that seems to have a mind of its own it would be prudent to remove the bulbs and bulb holders and clean the contacts. Sometimes it the bad contact that causes a current imbalance.

The rear tail light assembly is quite a horrid design. For each bulb there is a set of contacts between the holder and the flexible PC board and between the bulb and the holder. Than there is the main connector for the harness on the flexible PC board. Lot of potential for things to go wrong and they do.

Regards,

Boris Mohar

Got Knock? - see: Viatrack Printed Circuit Designs (among other things)

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void _-void-_ in the obvious place

Reply to
Boris Mohar

Don't I know it... My right rear brake light refuses to work. I've replaced the bulbs, fiddled with the connections, etc... as much as one can do squeezing into the little access space. Going to have to pull it out and work it over proper.

Reply to
clay

If you're lucky enough to have a garage, and it isn't full of other crap.

I did say something shiny behind you helps, I suppose in the dark any sort of wall is shiny enough.

Reply to
James Sweet

Yeah, replace the harnesses in both hinges, you pretty well nailed it down. It isn't particularly difficult or expensive.

Reply to
James Sweet

Yep, even different brands of otherwise identical bulbs can do it, the sensor is very sensitive, too much so.

Reply to
James Sweet

Check the connector that plugs into the light assembly. Sometimes the one or more of the contacts will wear right through the printed circuit board pads that make the contact with the connector pins. I repaired few with adhesive backed copper tape from stained glass supplier and some careful soldering.

Regards,

Boris Mohar

Got Knock? - see: Viatrack Printed Circuit Designs (among other things)

formatting link

void _-void-_ in the obvious place

Reply to
Boris Mohar

Not really -- the old deadman-switch over-ride (toolbox on brake pedal.) All you need is enough pressure to drop the pedal far enough. Of course, it does take bit of time (five-ten minutes) to check everything but not hard.

Backing into the garage and tapping the brakes (especially with a convex traffic mirror positioned properly) but I don't have a garage....

Reply to
byrocat

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