Low Beam electrical problem, switch or relay? & FOG LIGH

[Savage_one]

Hey guys, my 1984 528e's low-beam headlights wont turn on with the switch. I've jumped 30/87 on the relay-connection and the low-beams turn on. I've tried using all the other similiar relays and they still won't come on, and the relays are good they still work on the other functions.

My fog lights were doing the same, but they mysteriously started working after jumping 30/87 like i did on the low-beams. ???

Is it a loose/corroded connection, dirty switch contact or the relay?

Also, I've heard about this fog-light wire splicing where the fog lights can come on whenever u want them, like the running lights, anyone know how to do it?

Thank you very much!

[RonW]

Do your high beams work?

If so, check out pin 87 of the high beam relay. Pin 85 of both the low beam and the fog light relay is the low side of the relay's coil, and is connected to pin 87 of the high beam relay.

This is why turning on the high beams turns off the low beams and the fog lights; turning on the high beams pulls pin 87 high, which prevents the low beam and fog light relays from turning on.

Turning off the high beams removes voltage from pin 87. This causes the high beam filaments to act as a ground, so the low beam and fog light relays turn on, assuming the light switch is on.

According to the ETM, there are three white & red wires at pin 87 of the high beam relay:
-A thick wire that goes to the high beams.
-A thin wire which goes to pin 86 of the low beam relay.
-A thin wire which goes to pin 86 of the fog light relay.

My first guess is that those two thin-wire connections are bad. Break out your voltmeter and check that first.

[Savage_one]

Thanks! I think that makes sense because currently the high-beams DO work, and they DONT turn off the fog-lights.

I do have a multi-meter but don't know what setting to use or what reading to look for.

[Savage_one]

Okay I was looking at the lights while testing and it turns out the High Beam bulbs work, but when high-beams are switched on, the Low Beams come on instead.

[RonW]

Okay I was looking at the lights while testing and it turns out the High Beam bulbs work, but when high-beams are switched on, the Low Beams come on instead.

Ok, so let me see if I have this straight:

• You tested the high beam bulbs (the ones with only two spade connectors, not three) and they work.

Questions:
-How did you test them?
-Did you actually get them to illuminate as installed in the car, or did you do some sort of continuity test?
-Did you test all four bulbs (they all have high beam filaments), or just the two-connector ones?

• You turn on the headlight switch, and nothing comes on. You push the turn signal lever to turn on the high beams, and the low beams come on.

Questions:
-Did the blue high beam indicator in the instrument cluster turn on?
-Are you sure the low beams came on, or could it have been just the high beams in the outer bulbs?
-Once you have the headlight switch on and the turn signal stalk pushed, can you turn on the fog lights?

[Savage_one]

Okay, I've tested that all lights work by jumping power across the 30/87 relay connections, with the lights installed. I've even plugged in my brand new Low Beam headlights and they act the same.

So, putting the Light Switch to Low Beams gives me nothing, except it allows the fog lights to come on, and it does allow the turn signal to "flash" the high-beams, and the instrument cluster light does come on indicating high-beam.

But putting the Light Switch to High Beam turns on both sets of head-lights (and keeps fog lights on), and no I'm not sure if it's the High or Low beam filaments that are coming on.

And the connections in the fuse box and lamp sockets look good.

This electrical problem is the only thing holding me back on this car...

[RonW]

If this were my car, I'd break out my multimeter and start testing.

If you remove the high beam, low beam, and fog light relays, you should find that pin 30 of each socket is at 12V at all times, even if the car is off.

If you turn on the low beams with the ignition on, pin 86 of the low beam relay socket should be at 12V.

If turn on the fog lights at this point, pin 86 of both the low beam relay socket and the fog light relay socket should be 12V.

If you turn on the high beams at this point, pin 86 of all the relay sockets should be at 12V.

If you turn your car off and use your multimeter as an ohmmeter, Pin 85 on the fog light and low beam sockets should be connected to pin 87 of the high beam relay socket.

[jrlltmb2003]

Hey guys, my 1984 528e's low-beam headlights wont turn on with the switch. I've jumped 30/87 on the relay-connection and the low-beams turn on. I've tried using all the other similiar relays and they still won't come on, and the relays are good they still work on the other functions.

My fog lights were doing the same, but they mysteriously started working after jumping 30/87 like i did on the low-beams. ???

Is it a loose/corroded connection, dirty switch contact or the relay?

Also, I've heard about this fog-light wire splicing where the fog lights can come on whenever u want them, like the running lights, anyone know how to do it?

Thank you very much!

[jrlltmb2003]

I have a 84 528e,the headlights will not go on ,nor the brights,nor the fogs,{im in the dark here}help.which relays can i check,fuses ok

[RonW]

I have a 84 528e,the headlights will not go on ,nor the brights,nor the fogs,{im in the dark here}help.which relays can i check,fuses ok

The low beam relay, the high beam relay, and the fog light relay. The lid of your fusebox has them labeled.

But it sounds like the light switch is the problem. When you pull the turn signal toward you to flash the high beams, do they actually go on? Does the high beam indicator turn on?