535i brakes and tail light help

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Watut
Posts: 36
Joined: May 10, 2021 12:23 AM
Location: Calgary

535i brakes and tail light help

Post by Watut »

Hey guys, i recently acquired an 86 535i. Couple issues I'm trying to sort out.

The brakes were soft and i tried bleeding them which showed a blown hose from the side of the reservoir and disappears into the firewall. Where does this hose go?

Also, my brake lights, rear signal lights and back up lights do not work. But the tail lights work when i turn on the headlights. Any ideas?
Mike W.
Posts: 26872
Joined: Feb 12, 2006 12:00 PM
Location: California Whine Country

Re: 535i brakes and tail light help

Post by Mike W. »

First part is easy. They used the same reservoir for both the brakes and the clutch. The line going into the firewall should be the one about halfway up the reservoir and goes to the clutch master cylinder, which is mounted to the pedal assembly. That's so you lose clutch before brakes. If you have to replace that hose do use brake fluid specific hose, fuel line can expand with brake fluid and leak. Also be careful if you have to remove the line from the clutch M/C, it's got an angled plastic connector that connects to the soft line, and goes into the M/C. It's easy to crack at the bend.

Part 2. Check fuses. There are at least 2 and possibly as many as 4 fuses that feed different functions. Also check grounds at the taillight assembly. Usually it's the brake lights that are the problem, they used an odd ground with a piece of sheet metal folded over another piece of sheet metal for grounding. Over the years it's been known to conduct poorly. Oversimplifing some, there are 4 different switches that are turning the respective lights on, although a bad ground might account for all of it.
Watut
Posts: 36
Joined: May 10, 2021 12:23 AM
Location: Calgary

Re: 535i brakes and tail light help

Post by Watut »

Thanks for that mike. I will have a look tomorrow. Also my speedometer and odometer don't work at all. Where should I look for an issue here? Speed sensor in rear diff? Gears in cluster?
Blue Shadow
Posts: 10195
Joined: Feb 12, 2006 12:00 PM
Location: SE PA

Re: 535i brakes and tail light help

Post by Blue Shadow »

Gears in the cluster are for a working speedo but no odo.

Individual lights in rear cluster can be bad contact between the non-conductive zinc plated conduction strips on the cluster and the lamp housing. But missing all those lamps probably isn't that crappy electrical connection. German engineers thought that was a good idea???
Last edited by Blue Shadow on May 12, 2021 1:20 AM, edited 1 time in total.
MisterFixit
Posts: 964
Joined: Jul 21, 2006 5:01 PM
Location: Golden, Colorado

Re: 535i brakes and tail light help

Post by MisterFixit »

Watut wrote: May 10, 2021 12:26 AM Hey guys, i recently acquired an 86 535i. Couple issues I'm trying to sort out.
Congratulations on your recent acquisition, and welcome to the forum! Also my car, what color?
Also, my brake lights, rear signal lights and back up lights do not work. But the tail lights work when i turn on the headlights. Any ideas?
^^ Good suggestions all, these guys know what they are talking about... ^^

If you still have issues with the lights in back after checking the grounds and fuses, I will be glad to help - it's kind of my passion and area of expertise.
Also a good idea to check inside the white bulb holders (sockets), and at the metal conducting strips where they make contact next to each light... these areas are notorious for corrosion inside and outside of the sockets. This will dim or kill the bulb's output. Especially look at the left brake light, that one is usually the first to go.

If you get everything working again, and still want them brighter, I can definitely help there. Give me a shout any time. I have plenty of upgrades I am happy to share. All safe and effective at making the lights bigger, brighter, and more reliable.

Andy
Watut
Posts: 36
Joined: May 10, 2021 12:23 AM
Location: Calgary

Re: 535i brakes and tail light help

Post by Watut »

Thanks for the welcome. It's black. Can i add pictures on here?

I did some testing yesterday. For the turn signals, i definitely have power at the strips in the taillight so the problem has to be inside the white connector. I will try the brake lights next but first im waiting on the reservoir to clutch master hose. $40 at the local bmw dealership.

Reverse lights dont have power back there, ill have to figure those out too
MisterFixit
Posts: 964
Joined: Jul 21, 2006 5:01 PM
Location: Golden, Colorado

Re: 535i brakes and tail light help

Post by MisterFixit »

Watut wrote: May 11, 2021 8:32 PM Thanks for the welcome. It's black. Can i add pictures on here?
Yes, BUT you have to upload them to a hosting site, then link with a url or web page; whichever works better. Buttons for this are between the subject line and the message area.
I did some testing yesterday. For the turn signals, i definitely have power at the strips in the taillight so the problem has to be inside the white connector. I will try the brake lights next but first I'm waiting on the reservoir to clutch master hose. $40 at the local bmw dealership.
I have a ton of these white bulb sockets. New and decent condition used. A tip- familiarize yourself with the different styles - one takes big bright bulbs, for turn, reverse, brake lights; the other only takes the small 5-10 watt tail light bulb. You can't mismatch them in the light, but you CAN mismatch the bulbs, which can lead to melting and much sorrow. NEVER put a higher wattage bulb in the tail light socket (bottom center).
Reverse lights don't have power back there, ill have to figure those out too.
Could be the fuse (easy), the switch on the tranny (PIA to replace), or maybe (like on my car) the wiring to the switch. Connectors are under the shift boot in front of the stick. The leads to/from the switch should be green/white (power) and blue/white (to lights). Shorting these should light the reverse lights.

Which lights DO work, so far? I'd start by inspecting the socket internals and outer 'finger tabs) for all that are MIA, then the contact areas under the tabs; look for corrosion, rusty / perforated metal parts. And clean all the dirt off the bulbs. And clean the inside ... well, maybe later.

Good luck, let me know if you need some sockets / advice on rear lights.

Andy
Watut
Posts: 36
Joined: May 10, 2021 12:23 AM
Location: Calgary

Re: 535i brakes and tail light help

Post by Watut »

Let's see if this works. She's got 206 000 miles but was in decent condition and priced right so i couldn't let her go to the wreckers

Image

The tail lights work, when you turn on the head lights.

Turn signals have power but the bulbs don't work

Reverse lights don't work. Do you know which fuse controls this?

Brake lights i will have to check

Do you recommend i clean my bulb contacts and possibly doing the octopus mod before i go furthere
MisterFixit
Posts: 964
Joined: Jul 21, 2006 5:01 PM
Location: Golden, Colorado

Re: 535i brakes and tail light help

Post by MisterFixit »

Watut wrote: May 12, 2021 5:33 AM Let's see if this works. She's got 206 000 miles but was in decent condition and priced right so i couldn't let her go to the wreckers.

https://ibb.co/4T4XFGX
Looks like nice paint in the picture, though it does not appear in the post - I had to copy and paste in a new window. I edited your link with the "url" tags, seems to work now when you click.
The tail lights work, when you turn on the head lights.
As they should - on either the f1rst or second click. I suppose they are fairly dim, correct? This also powers all four side markers, front (parking) lights, rear license plate, instrument lights, controls for heat, hazard flasher switch, clock, ash tray, etc. - lots of switches and stuff inside the car.
Turn signals have power but the bulbs don't work
Do front turn signals blink? Normal or 'hyperflash' fast blink? If you swap the reverse light sockets with bulbs into the turn signal, does that get the turns to work?
Reverse lights don't work. Do you know which fuse controls this?
Fuse chart is on the fuse box cover - lower left corner, fuse 6 shows it as "rev.li." Check wiring as well, it may be something is unplugged (the pair of leads under the shift boot).
Brake lights i will have to check.
Yes, you will want them to work! I suggest getting a helper; or you can back into a space in front of a full glass window / storefront, then look in your mirrors at the reflection of the tail lights as you push the brake (key on, of course). You'll want all three to work.
Do you recommend i clean my bulb contacts and possibly doing the octopus mod before i go further?
Well, yes, of course I do. Clean all surface corrosion off with a tiny wire brush (I use an ancient Dremel 'moto-tool' on a low speed) until the metal contacts are more or less shiny. You may not get to silver, that's OK (don't go nuts). Sometimes the metal just turns dark with age. I usually remove the contacts from the white sockets (bulb holders) to clean and polish, but you may not want to try that... I've been doing this for some years.

The Octopus solution is a good one, replacing the crappy connections with hard wiring directly to the lamps, but there may be a simpler one that will do the trick... for less money. The Octopus is a 'take no prisoners' solution, and WILL give you full strength lighting, as long as any fuse / rev. light power issues are resolved. Either way, there are upgrade options with both approaches, adding tail and brake bulbs within the stock light. No hacking, no damage, just lots more light. I like to think of it as making every square inch of the light useful.

Let me know if you want more information on any of these suggestions. Email is best, or PM, or research my posts on the forum.

Andy
Mike W.
Posts: 26872
Joined: Feb 12, 2006 12:00 PM
Location: California Whine Country

Re: 535i brakes and tail light help

Post by Mike W. »

You linked to the page not the image itself.

Image
Watut
Posts: 36
Joined: May 10, 2021 12:23 AM
Location: Calgary

Re: 535i brakes and tail light help

Post by Watut »

MisterFixit wrote: May 12, 2021 10:46 AM
Watut wrote: May 12, 2021 5:33 AM Let's see if this works. She's got 206 000 miles but was in decent condition and priced right so i couldn't let her go to the wreckers.

https://ibb.co/4T4XFGX
Looks like nice paint in the picture, though it does not appear in the post - I had to copy and paste in a new window. I edited your link with the "url" tags, seems to work now when you click.
The tail lights work, when you turn on the head lights.
As they should - on either the f1rst or second click. I suppose they are fairly dim, correct? This also powers all four side markers, front (parking) lights, rear license plate, instrument lights, controls for heat, hazard flasher switch, clock, ash tray, etc. - lots of switches and stuff inside the car.
Turn signals have power but the bulbs don't work
Do front turn signals blink? Normal or 'hyperflash' fast blink? If you swap the reverse light sockets with bulbs into the turn signal, does that get the turns to work?
Reverse lights don't work. Do you know which fuse controls this?
Fuse chart is on the fuse box cover - lower left corner, fuse 6 shows it as "rev.li." Check wiring as well, it may be something is unplugged (the pair of leads under the shift boot).
Brake lights i will have to check.
Yes, you will want them to work! I suggest getting a helper; or you can back into a space in front of a full glass window / storefront, then look in your mirrors at the reflection of the tail lights as you push the brake (key on, of course). You'll want all three to work.
Do you recommend i clean my bulb contacts and possibly doing the octopus mod before i go further?
Well, yes, of course I do. Clean all surface corrosion off with a tiny wire brush (I use an ancient Dremel 'moto-tool' on a low speed) until the metal contacts are more or less shiny. You may not get to silver, that's OK (don't go nuts). Sometimes the metal just turns dark with age. I usually remove the contacts from the white sockets (bulb holders) to clean and polish, but you may not want to try that... I've been doing this for some years.

The Octopus solution is a good one, replacing the crappy connections with hard wiring directly to the lamps, but there may be a simpler one that will do the trick... for less money. The Octopus is a 'take no prisoners' solution, and WILL give you full strength lighting, as long as any fuse / rev. light power issues are resolved. Either way, there are upgrade options with both approaches, adding tail and brake bulbs within the stock light. No hacking, no damage, just lots more light. I like to think of it as making every square inch of the light useful.

Let me know if you want more information on any of these suggestions. Email is best, or PM, or research my posts on the forum.

Andy

Thanks for all your help andy. I tried swapping the tails and turn signals. The signals work. I will try cleaning the bulb holders and swapping in new bulbs and see where that gets me. Brake lights and reverse lights still non-working.

Going to the fuse box, many of the fuses were the wrong amperages so i will be replacing all of those as well before doing further testing so that i have a proper baseline.
Watut
Posts: 36
Joined: May 10, 2021 12:23 AM
Location: Calgary

Re: 535i brakes and tail light help

Post by Watut »

MisterFixit wrote: May 12, 2021 10:46 AM
Watut wrote: May 12, 2021 5:33 AM Let's see if this works. She's got 206 000 miles but was in decent condition and priced right so i couldn't let her go to the wreckers.

https://ibb.co/4T4XFGX
Looks like nice paint in the picture, though it does not appear in the post - I had to copy and paste in a new window. I edited your link with the "url" tags, seems to work now when you click.
The tail lights work, when you turn on the head lights.
As they should - on either the f1rst or second click. I suppose they are fairly dim, correct? This also powers all four side markers, front (parking) lights, rear license plate, instrument lights, controls for heat, hazard flasher switch, clock, ash tray, etc. - lots of switches and stuff inside the car.
Turn signals have power but the bulbs don't work
Do front turn signals blink? Normal or 'hyperflash' fast blink? If you swap the reverse light sockets with bulbs into the turn signal, does that get the turns to work?
Reverse lights don't work. Do you know which fuse controls this?
Fuse chart is on the fuse box cover - lower left corner, fuse 6 shows it as "rev.li." Check wiring as well, it may be something is unplugged (the pair of leads under the shift boot).
Brake lights i will have to check.
Yes, you will want them to work! I suggest getting a helper; or you can back into a space in front of a full glass window / storefront, then look in your mirrors at the reflection of the tail lights as you push the brake (key on, of course). You'll want all three to work.
Do you recommend i clean my bulb contacts and possibly doing the octopus mod before i go further?
Well, yes, of course I do. Clean all surface corrosion off with a tiny wire brush (I use an ancient Dremel 'moto-tool' on a low speed) until the metal contacts are more or less shiny. You may not get to silver, that's OK (don't go nuts). Sometimes the metal just turns dark with age. I usually remove the contacts from the white sockets (bulb holders) to clean and polish, but you may not want to try that... I've been doing this for some years.

The Octopus solution is a good one, replacing the crappy connections with hard wiring directly to the lamps, but there may be a simpler one that will do the trick... for less money. The Octopus is a 'take no prisoners' solution, and WILL give you full strength lighting, as long as any fuse / rev. light power issues are resolved. Either way, there are upgrade options with both approaches, adding tail and brake bulbs within the stock light. No hacking, no damage, just lots more light. I like to think of it as making every square inch of the light useful.

Let me know if you want more information on any of these suggestions. Email is best, or PM, or research my posts on the forum.

Andy

Thanks for all your help andy. I tried swapping the tails and turn signals. The signals work. I will try cleaning the bulb holders and swapping in new bulbs and see where that gets me. Brake lights and reverse lights still non-working.

Going to the fuse box, many of the fuses were the wrong amperages so i will be replacing all of those as well before doing further testing so that i have a proper baseline.
Watut
Posts: 36
Joined: May 10, 2021 12:23 AM
Location: Calgary

Re: 535i brakes and tail light help

Post by Watut »

Mike W. wrote: May 13, 2021 12:53 AM You linked to the page not the image itself.

Image
Thank you for fixing that for me
MisterFixit
Posts: 964
Joined: Jul 21, 2006 5:01 PM
Location: Golden, Colorado

Re: 535i brakes and tail light help

Post by MisterFixit »

You're welcome.
Good luck with the fuses, it's a good idea to replace them once in a while anyway.
Good thing you caught the incorrect fuse ratings... sometimes an amateur will think they are solving a problem by sticking a bigger fuse in, the real problem goes begging for a solution that is safe.
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