Low beam check panel keep lighting up

[Ceeker]

I have an 87 vert and every time I put the headlights on the check panel shows I have a low beam error. The thing is, there isn't any problem. Alll my lights work.

I understand that the check system is built into the circuit board under the fuse box. Has anyone ever had this problem and if so how was it corrected.

help would be appreciated. thx.

[DaveSmed]

Check control's lamp monitoring is usually pretty robust. Insufficient current draw from a dirty connector or something is usually what upsets it.

Barring that, did you do any work around the pedal box under the dash? The ground for the headlight check relay is under there. The aux fan relays share the same ground, so if the aux fan works correctly, that's probably ok.

[Ceeker]

Check control's lamp monitoring is usually pretty robust. Insufficient current draw from a dirty connector or something is usually what upsets it.


Barring that, did you do any work around the pedal box under the dash? The ground for the headlight check relay is under there. The aux fan relays share the same ground, so if the aux fan works correctly, that's probably ok.

I thought maybe the low beam fuse isn't making sufficient contact with the fuse box? I recall it was doing this for a while and then stopped until I removed the fuse and think it disturbed it.

I haven't touched anything under the kick panel. I was thinking about that relay actually and thought maybe the relay may have something to do with it. My aux fan at some point was partially seized due to insufficient use. But I unseized it with a few spins and then ran it often. it was noisy at first but now that's all gone and runs fine.

[Mo Brighta]

low beam issue?

I have an 87 vert and every time I put the headlights on the check panel shows I have a low beam error. The thing is, there isn't any problem. All my lights work.

If there is a weak connection, that may cause reduced current to the lamp on that side and throw a fault.

I wonder if you may have a weak ground or corrosion in a connector. Could also be in the fuse box, my E28 is notorious for weak fuse contacts. Yours is different, but corrosion knows no bounds, and BMWs are particularly sensitive to corrosion.

Do this- with the key to 'run' and engine off, turn on the lights to low beam, and go out in front of the car about 50 feet away. Look very carefully at the two lights, does one seem brighter than the other? You may want to move around a bit from side to side, up and down, to get a good idea of their output relative to each other.

Try unplugging / replugging the headlight connector a few times, that may scrape off any corrosion and get better voltage to the light.

Good Luck, and let us know.

[Ceeker]

If there is a weak connection, that may cause reduced current to the lamp on that side and throw a fault.

I wonder if you may have a weak ground or corrosion in a connector. Could also be in the fuse box, my E28 is notorious for weak fuse contacts. Yours is different, but corrosion knows no bounds, and BMWs are particularly sensitive to corrosion.

Do this- with the key to 'run' and engine off, turn on the lights to low beam, and go out in front of the car about 50 feet away. Look very carefully at the two lights, does one seem brighter than the other? You may want to move around a bit from side to side, up and down, to get a good idea of their output relative to each other.

Try unplugging / replugging the headlight connector a few times, that may scrape off any corrosion and get better voltage to the light.

Good Luck, and let us know.

thanks for your input. I think I'll wait for dusk to do that test and will let you know. My car sat for many years on and off; guy hardly drove it in the 14 year ownership. When I first got the car and turned the lights on the check panel lit up with the fault. Went outside and saw no lows on, on the drivers side. So I thought maybe the bulb -changed the bulb and still no response. then when I changed the cluster-because the high beam indicator was out and speedo was dead tried the lights - high beam indicator, heard a click and then went outside to check and all the lights were on. I was like huh? that was weird. I checked the fuses for contact and everything seemed fine. So for a while it did this; lights on check panel on. Then, suddenly this became intermittent. Sometimes it wouldn't come on for a long while, sometimes not at all. I thought maybe it just figured itself out like the drivers side lows being out. Then one day I removed the fuse and immediately after replacing it came right back on again just as before.

so, with this being said. I will check, check the contacts. maybe even replace the low relay incase something is buggy with it.

Update:

I didn't see any difference in the light output; I replaced the low beam relay with a spare I had just for added measure. I removed the drivers side low beam pod and removed the plug; I checked the males on the bulb side - ok; I then checked the harness side and found the yellow to be a tad green. I cleaned if off, pinch the prong to make a better fit better, and installed everything back. But there is no change with the check panel. It comes on like clock work. I suspect there may be corrosion on the circuit board seeing in the earlier models the check circuit is integrated in the fuse box circuit board. I would suspect this is where the weak link might be.

thanks - Ernie

[Ceeker]

ok, here is an update: I flipped the lights on and off to trigger the low beam check control. As usual the panel lit up. I did this a few times shutting the car off and re-starting it. Still came on.

what I noticed was this: as I turned on the lows I heard the idle drop ever so slightly; typical when there is draw on the electrical system. yaknow, on a cold day and you have every electrical option on you hear the fan speed lessen.

After a few tries I started the car again and turned on the lows, this time - no draw and no dip in idle and the check control panel didn't light up. so just out of my curiosity I did this a good few times and still no check control.

any input would be welcomed. :-)

Ernie

[DaveSmed]

That is really odd. Remove K1, K2 or K6 (whichever is easiest) and measure voltage with the negative lead on that little allen bolt under the relays, and the positive on the large lug on the back of the alternator with the headlights off, on, and if you can on w/o the idle drop.

That description is kind of the opposite of what I would expect to happen.

[Ceeker]

That is really odd. Remove K1, K2 or K6 (whichever is easiest) and measure voltage with the negative lead on that little allen bolt under the relays, and the positive on the large lug on the back of the alternator with the headlights off, on, and if you can on w/o the idle drop.

That description is kind of the opposite of what I would expect to happen.

ok, I think my car is possessed. sheesh...I did the sequence again and now I don't have draw. but the check panel still comes on. I took out the sealed beams and installed ellipsoids..much better lighting.

I'll try what you suggested just for shits and giggles..