Dash, side markers and right parking lights

[Visions]

Hello,,,89 535i,,, have a bit of a problem,,, the dash gages, climate control lights, license plate and right parking lights front and back went out at the same time... also the side markers are out all the way around and I am not sure if those went out at the same time...

I have checked the LKM by swithcing with my other car and it doesn't help...

Fuses all look fine and I even changed #5 just to be sure and it didn't help...

I have read about the trunk being a problem spot... but I looked for the junction near the left of the side trunk lid and all I saw were wires... is there a junction somewhere near or back farther that causes problems?

I tried new bulbs in parking and side markers but nothing has helped...

Thanks for your help!... It's supposed to be decently warm tomorrow so I would like to get this taken care of before winter really kicks in...

[Javier]

funny thing is that they use different contacts in the Light switch for the interior or park lights, so I can hardly believe the issue is in the switch.

Make a good inspection on the fuse F5, check with a meter is possible, verify fuse socket is OK, and finaly, as a last resource, check for voltage at the Red/Blue wire coming into the Lights Switch.

Javier

[Visions]

Javier,, on rear parking I checked for voltage and didn't have any... the break and turn showed voltage...

Both the old and new fuse was tested to be good...

For the socket I should have voltage across it.... Now what if I don't?

[Javier]

no, there should be no voltage across, but you should have voltage from any of the fuse terminals to ground (car body metal).

If you remove the fuse and light switch is tuned on, yes there should be voltage across. If not, also check voltage to ground from both pins holding the fuse, one of them should be 12Vdc, if not, the problem is that the fuse is not getting power (cut wire?) and you should debug the circuit up stream towards the battery.

If you have voltage at one pin and still no voltage across, then you have an open circuit down stream, probably at the wire going from the fuse to the light switch (Red/Blue one).

Javier

[Visions]

is it possible to have one of the lights short out the circuit and not blow the fuse?

[Javier]

There is no way to have an over current without blowing them. The question is: Is there a short to ground? As it is not the only possible fault. The short-circuit to ground is a fault in which the positive wire feeding a load contacts the negative wire (ground in cars) before reaching that load (in or after the load, it is no longer a positive wire). This short-circuit is equivalent to have a 0 resistance load (thus his name) and as load current is the quotient of voltage over resistance, current pretends to rise to infinitum blowing the fuse. Another fault blowing fuses is Overload, it is caused by having in a circuit so much loads, so the sum of their currents is over the total current the fuse can allow. Fuse operation is based in inverse curves, it means the more the current the shorter time it takes to blow it, some times, over currents are really small and it can takes minutes (or hours) of overload operation to blow the fuse. This faults are specially risky, as if the fuse is not properly rated to protect the wires involved in the circuit, it can overheat the wires causing fires, or insulation damage that will lead to short-circuits and major damages on the surroundings.

A third possible type of fault does not blow fuses at all, it happens when the circuit opens, not carrying power any longer to the load. It is the case when wires are severed, pulled out of the connectors, or simply corroded in the terminals. If the exposed wires after the rupture of the circuit never contacts the ground, there will never be a short nor blown fuses.

These were all single circuit faults, but as you may guess, in a multiple circuit harness, there is also the possibility of having short-circuits (as straight connections) between wires of different circuits, but as not being at different voltages (both at 12 V, at 12 V after a switch operation, or both at ground level) there may not be high currents nor fuse operations. This causes things to work funny, as turn on wipers when lights are turned on, or similar gremlins.

In our e34, there is a typical source of electrical problems as it is the left trunk lid hinge harness. It generally involves several severed wires, some times short-circuited between them, and almost never involving blown fuses, but believe me, there is a lot of issues it crete in reverse and interior lights, and in the central locking system.

Javier

[Visions]

You have been a great help and I definately appreciate your time and knowledge...

One last thing... I didn't see a wiring harness on or near the trunk lid hinge.... only see taped wires.... is it back behind the carpeting?

I am off of work tomorrow and will use the knowledge you gave me to run down this problem...

Thanks alot

Visions

[Paul in NZ]

wires comes from under the parcel shelf and onto lh hinge ussually covered with black plastic sheath on the hinge itself.It is this sheath which causes the problem by bending the wires in a tight radius

[Javier]

You may notice that opposite to the right, left one has a black plastic cover concealing the wire harness connecting body wiring to the lid wiring. There are wires for reverse lights, rear fog lamps, license lamps, interior trunk lights and trunk power lock. You talked about taped wires, so if your car doe not look like the pictures, then guess somebody did repair the hinge harness before.

As you are not blowing fuse F5 and your description said interior signals lights and license and parking lights are out, being them controlled by different contacts in the light switch (making circuits independent after light switch), bet your problem is before light switch.

Javier

[Visions]

Thanks guys,,, I will check out the hinge in the morning,,, no wonder I couldn't find the harness...

Also Javier,,, I pulled F5 and tried to get V to ground but it didn't read a thing... but maybe I didn't have a good ground...

[Javier]

I pulled F5 and tried to get V to ground but it didn't read a thing...

When you pull out the fuse, one of the connecting clips has no voltage (the one going to the yellow wire / protected clip), the second clip should have voltage (the one going to the red wire / feeding clip).

Under the fuse box, there is a splice (X1.1) that connects several red wires going each to its corresponding fuse. Fuses F4, F5, and F6, among others, are feed from this splice. If you have power to F4 and F6 circuits, and do not get voltage at F5 feeding clip, the only possible explanation is that the wire going from X1.1 to F5 feeding clip is opened, I would say it is corroded in the splice or in the crimp at the feeding clip, this of course, based in a proper reading of "No voltage" at the clip, that includes having cleaned any surface corrosion in the clip itself, that may be deteriorating the connection of the test probe.

There is a simple trick to confirm the feeding clip of F5 is not getting power, or is heavily corroded. With the fuses installed, jump with a wire the F4 and F5 fuses, I mean, connect the fuse filaments one to the other (see picture). If the lamps depending on F5 light UP, then the problem is F5 not getting power.

You will have to disconnect the battery, disassemble the fuse cradle, and inspect carefully the red wire going into F5, and its terminals.

Javier

[Visions]

Javier you are wealth of information!... I have a feeling the F5 fuse is the problem and I will use your info to test it further tomorrow...

Today I took the plastic cover off the left trunk hindge and there is no junction... wires are taped up very well,,,moved them around alot an nothing... Inside trunk lid lights work so I don't know if they are connected to F5...

All sidemarkers are badly corroded and will need to be replaced...

Thanks again for your help....

[Javier]

but license plate lights are hooked to F5.

Javier

[Visions]

Jumping the fuse didn't help... but

What I noticed while playing with the switch is that it has some shorts in it... If I only turn on the parking lights I can wiggle the switch and the left parking lights go off... If I turn on all the lights I can wiggle the switch and erratically the left parking lights go out and or all head lights... So I believe this is the root of the problem... Too bad I cant wiggle the switch to get the other lights to come on just to prove it... so now I will change the switch... Looks like it wont be easy... You have any links on how to do it?

Thanks again

[Javier]

Here you are. Easy job.

Javier

[Visions]

The switch was the cure... Right Parking lights, license plate lights and Dash lights now all work... couldn't have been any easier changing the switch... Lucky the switch had a noticable short for the other lights or I may not have thought of the most simple reason they were out...

Thanks Javier for your help...

[franan]

hi javier do you have any idea turn off the car removed the key from the ignition still running.

[BillionPa]

turbo timer?

[Hornswoggler]

My fuse 5 keeps blowing and giving me the same symptons. I have replaced the light switch and the fuse a couple of times (with 10 amp replacement) and no success. I took some voltage readings across the light switch connector now need to make sense out of them :)

If anybody has ideas, lemme know! TIA