Flasher / Indicator / turn signal intermittent: possibly a relay issue?

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ColinC.sg
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Flasher / Indicator / turn signal intermittent: possibly a relay issue?

Post by ColinC.sg »

Hi all, I have an ‘81 635 rhd…
Have been having intermittent problems with the turn signals/indicators (and hazard lights)
They work when I first start driving but after some time - ranging from 10 mins to maybe 30 mins, the indicators (and hazard lights) suddenly all don’t function… indicators and hazard lights…
After trying to trace this issue, we managed to find out that the flasher relay ( located under the steering column above the right knee) was a little “sticky”…
When the signals stopped functioning, a couple of taps/light knocks on the relay will somewhat reset/restart the flashing.
Also I did thing that the flashing speed was a little fast while it worked.

Anyone can help give some advice on what could be the root cause or is it just in need of a replacement relay? Or could it be that the hazard light switch is the cause of the problem… and what else should I check?
And where I could find suitable suppliers..
Thanks in advance.
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hornhospital
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Re: Flasher / Indicator / turn signal intermittent: possibly a relay issue?

Post by hornhospital »

Replace the relay. You might consider an electronic version rather than the electromechanical OEM version. The only disadvantage is that it will flash regardless of failed bulbs/connections, something that the OEM unit will sometimes "warn" you about by failing to flash if a bulb fails.
Ken Kanne
'84 633CSi "Sylvia"; '85 635CSi "Katja";'85 325e "Hazel Ann"; '95 M3 "Ashlyn"
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ColinC.sg
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Re: Flasher / Indicator / turn signal intermittent: possibly a relay issue?

Post by ColinC.sg »

Thanks hornhospital…
I did further checks… the relay looked quite new… and when checking back on my receipts for work done, i realised that I had a new one put in when i first acquired the car and got issues fixed… the signals were a little intermittent then as well i believe… This was about a year and a half ago….
Any further thoughts or advice?
TIA
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olympia57
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Re: Flasher / Indicator / turn signal intermittent: possibly a relay issue?

Post by olympia57 »

Diagnosing problems over the internet is notoriously difficult but ....
My first port of call would be the hazard flasher unit . As you can see all the circuits are connected to it so a total failure would suggest it as a possible culprit .
Image
These switches , in LHD format , are cheap but in RHD equivalent are pretty expensive and due to the construction the faces cannot be changed . This I discovered when mine recently failed and I purchased a new item from the Main Dealer .
I also had a problem with the original mechanical relay type flasher unit intermittently failing and changed over to an electronic one .
See here .
https://www.bmw2002faq.com/forums/topic ... ce/?page=1
One other point on the original flasher unit is that they are not very tolerant to mismatched or incorrectly rated bulbs . Not sure how old yours are but perhaps a fresh set would be advisable .
Good luck
Don
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1981 635 series 1
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ColinC.sg
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Re: Flasher / Indicator / turn signal intermittent: possibly a relay issue?

Post by ColinC.sg »

Hey Don,
Thanks for the advice and links.
I think I will have a look at an electronic unit.
Thanks
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cornwallis
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Re: Flasher / Indicator / turn signal intermittent: possibly a relay issue?

Post by cornwallis »

I’m having issues with both turn signals and hazard lights. They do not flash. Appears that the hazard switch and the turn switch on the LHS of steering column work, as the lights on the cluster turn on - but they do not flash intermittently as they should.

Looked at the ETM FOR 1985 635 CSi. See below.

Is flasher noted in schematic a relay or is it a separate solid state device that has the timer incorporated into the relay?? Appreciate any advice before I start looking for wires and relays under the dash. Thanks in advance!
IMG_3824.jpeg
IMG_3824.jpeg (329.03 KiB) Viewed 799 times
Also should I be cleaning the turn signal on the column - is it possible to clean the contacts?
Hector :twisted:
____________________________________________________________
1985 635 CSi, Auto
bpoliakoff
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Re: Flasher / Indicator / turn signal intermittent: possibly a relay issue?

Post by bpoliakoff »

on the early Euro cars everything you describe goes through the flasher button Check that first. They can gently be taken apart and cleaned and the contacts "nudged" to put on a little more more tension on the contact arms
81 Euro 635 M90 with motronic. Currently under a complete nut and bolt restoration. Pictures at
flickr.com/photos/bertsphotos.
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RossDinan6
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Re: Flasher / Indicator / turn signal intermittent: possibly a relay issue?

Post by RossDinan6 »

I have not dealt with the flasher circuit so any further statements may be BS.

Your attached ETM states "Solid State". which tells me it more than a relay. Flasher modules in simple times utilize a bimetalic strip which heats when switched on. As the temp rises the strip bends and opens the circuit. Now open the strip cools and closes turning on the lights. This heats the strip and it opens again. All this happens quickly resulting in the flashing.

German engineers in their infinite wisdom seem to have decided to make a not so simple electronic module to accomplish the same function. With that rant now posted:

Removing the flasher and installing a temporary jumper between terminals 49 and 49a would turn on the lights when the flasher switch is closed. I'd have to look at the complete diagram to see if I am missing anything.
Ross
'84 633 Dinan turbo
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Re: Flasher / Indicator / turn signal intermittent: possibly a relay issue?

Post by bpoliakoff »

A friend, adapted a NAPA solid state flasher with one wire change, I am not sure which ones , but it works well and not very expensive
81 Euro 635 M90 with motronic. Currently under a complete nut and bolt restoration. Pictures at
flickr.com/photos/bertsphotos.
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