Headlights ON if battery connected, won't turn off.

[84318i]

Hi,

My new to me 89 635csi has a problem I'd like to solve , if the battery is connected then the Low Beam headlights turn ON and stay on.
This works even without the Key being in the ignition at all, so obviously this is an issue

Any recommends on where to loo first on what would cause this? I haven't gotten a Bentley and ETM manual for this car yet, so wondering if there is anything I could quickly look at to see if it's an easy fix perhaps a relay or is there a Light module like in the E32/E34 cars?

Thank you in advance!

[dcains]

Pull relay K4 in the fusebox and see what happens. It's a relay that's used in several different locations, so pull one of the other matching relays, insert it where K4 was, and see if the lowbeams work normally.

[84318i]

Yep, will do that . Is the power supplied to the relay even when the key is not in the ignition ?

[1986series6]

Posted twice, sorry 'bout that.

[1986series6]

Here is the ETM for an 89. Pages 6312-0 & 6312-1, have the schematic for the headlight circuit.

http://wedophones.com/Manuals/BMW/19...g%20Manual.pdf

[84318i]

Thank you.

Pulled the headlight relay and the lights turned off (good).

Pulled another relay of the same kind and installed Into k4 spot and lights turned back on without key in ignition and headlight switch on (bad)

[ldk]

Pulled another relay of the same kind and installed Into k4 spot and lights turned back on without key in ignition and headlight switch on (bad)

I have an '86. That's how mine works. Twice I left the car with the light switch on and returned to a dead battery. I put a beeper in to warn when the door is open and the headlights are on.

[dcains]

My '85 Euro is similar. The headlights won't stay on, but the city lights and rear lights do with the key off. I do it all the time, but the LEDs don't draw many amps, and I have yet to kill the battery, even overnight. I need to install a buzzer, too.

[84318i]

That's strange ! Shouldn't you be able to turn the lights off though ?

The problem is the lights stay on even the headlight switch is in off position ...as long as the battery is connected the lights are automatically On if the relay is in place .

[carsnplanes]

That's strange ! Shouldn't you be able to turn the lights off though ?

The problem is the lights stay on even the headlight switch is in off position ...as long as the battery is connected the lights are automatically On if the relay is in place .

Do your fog lights turn on when your low beams are on when they are not supposed to be on?
The K4 relay has power available whenever the ign switch is in RUN or Start position, basically anytime the ign switch is not in the off position, but you still need a ground to pull the relay, and that comes from the light switch. Either you have a short to ground between the light switch and the K4 relay or your light switch is is always on ...evn though you think it is off.

[1986series6]

Jody,

I looked at the schematic for the lights. Can't figure out why the headlights stay on with ignition switch off.

Also--I didn't forget about detail. My buffer pad was dried out. I finally have a new pad installed.

If there's a really nice day coming up on a weekend, I'll call you if your available. If not, we'll do it first nice day in the spring.

Happy Thankgiving

Bob V

[dcains]

At this point, it sounds like the switch might be shorted to ground. I'd take it out, test it with a meter, and spray it with copious amounts of contact cleaner. If that fails, check the wiring and/or substitute another switch into the circuit.

[84318i]

Fogs don't turn on with headlights , just the low beams do this.

I'll pull the headlight switch out next and hope that turns the lights off when the relay is present .

These are 5 pin relays , can one from newer chassis be used like e34?

[carsnplanes]

Fogs don't turn on with headlights , just the low beams do this.

I'll pull the headlight switch out next and hope that turns the lights off when the relay is present .

These are 5 pin relays , can one from newer chassis be used like e34?

Sure, just make sure the 5 pins have the exact same pin #s and is laid out/pin arrangement, is the same between the two.

[DesktopDave]

I'm not sure if you solved this one yet, but I think both headlight circuits use unique relays in the late-model cars. Low-beams have a 5-pin normally off relay. The high beam uses a 'flip-flop' 5-pin instead, one leg is always switched on. If the relays were accidentally swapped, the low beams will always be on regardless of the headlight or ignition switch positions. The headlight switch only grounds the control side of the relays.

[carsnplanes]

Fogs don't turn on with headlights , just the low beams do this.

I'll pull the headlight switch out next and hope that turns the lights off when the relay is present .

These are 5 pin relays , can one from newer chassis be used like e34?

When did this issue start? Any maintenance done to the car just before this issue?

[84318i]

I'm not sure if you solved this one yet, but I think both headlight circuits use unique relays in the late-model cars. Low-beams have a 5-pin normally off relay. The high beam uses a 'flip-flop' 5-pin instead, one leg is always switched on. If the relays were accidentally swapped, the low beams will always be on regardless of the headlight or ignition switch positions. The headlight switch only grounds the control side of the relays.

That's interesting ! Thank you, will have to dig into it more and see if that's the case

When did this issue start? Any maintenance done to the car just before this issue?

No idea, purchased it this way and po didn't mention this issue .

[bmw6fan]

See if your high beams or fog lights will come on with the light switch off. If not your switch is probably good. Can you feel the relay clicking when you remove and install it? Check pins 30 and 87 for continuity. They should be open. If closed get new relay. Check pins 85&86 for voltage in relay base. If you have voltage then 85 is grounded. If no voltage. Check pin 87 for voltage to ground. Should be none there

[84318i]

30 to 87 is open . Will check pins 85 and 86 for voltage tomorrow .

[84318i]

Hi,

So I am revisiting the issue and just spent some time trying to resolve it and wasn't able to.

Here is what I've done to get this out of the way. High beam and low beam relays are 12v 20/30A 0332 204 401 5pin relays.
I've tried swapping them around and it made no difference.

CAR OFF, KEY OFF
If the relay is present then Low beam lights turn ON.
When I pull the relay and check for voltage on any of the pins in the fusebox socket I am seeing 12 volts on pin 30.
This is present on both High and Low beam sockets.

I went ahead and removed the headlight switch and tried another switch, no difference.
I also tried disconnecting the headlight switch completely, that made no difference either.

So, then I tried the following combinations.

Car is OFF, but Key is in the Accessories position and Headlight switch is OFF.
Votlage is present on both highbeam and low beam relay sockets on pins 30 and 87.

Car is OFF, key is in accessories position but now with the headlight switch ON
Voltage is ONLY present on pins 30, for both high beam and low beam relays.


Now, Car is ON and Headlight switch if OFF. If relay is present then Low beams turn ON.
Interestingly I don't see ANY voltage in any of the PINS in highbeam nor lowbeam sockets?!

Car is ON, Switch is ON
Turning High Beam switch ON, brings 12volts to pin 30 on the high beam relay.

[84318i]

Anyone?

[bmw6fan]

Pin 30 should be on at all times. Pin 87 should not be on unless relay is energized. I would concentrate on finding out where that power is coming from with the key off. Fuses 1,2,13,14 should kill the lights. I'd start pulling other fuses to see if that voltage is coming from somewhere else

[84318i]

I am afraid maybe there is some wiring issue/problem within the fuse/relay box. Pulling all the fuses 1,2,13,14 does not turn both low beams off, only turns ONE of them off when the key is not in ignition.

To confirm, pin 30 should be ON even with key off ?

[bmw6fan]

To confirm, pin 30 should be ON even with key off
Yes.Screenshot_2018-04-06-17-09-32.png
Screenshot_2018-04-06-17-09-32.png
Try unplugging that active check control unit