Donīt know if this is the right place to post it, but its meant as a help for anyone with BMW E21īs.
This post is made from a lot of information freely available on the web on numerous pages, but i thought it would be nice to collect everything in one place.
Electrically the E21 is not that advanced. But the turn signal can be quite a hell to get running properly. Many over the years has experienced this. The sinner is the hazard light switch.
My personal experience with this started when i drove my E21 home from purchase. I noticed that a piece of a wooden toothpick was sitting what appeared to be just besides the hazard light switch. I thought to my self "thatīs kindof nasty" so i tried to just flick it off with a finger. But as i did, suddently the turn signal lights didnīt work. And the toothpick was not just sitting next to the hazard light switch. It was lodged into the switch. As i got home with the car i removed the toothpick and it turned out that the hazard light switch was broken and couldnīt be turned off.
Now thing is that the fuse for the hazard light is also the fuse for the rest of the turn signal system. So pulling that wont work.
Also the hazard light switch is wired up with numerous wires, and pretty much connected to everything else electric in the car.
You will discover that if you turn on your turn signal arm to either right or left, and fiddle a bit with the hazard switch that suddently the turn signal works. (that is where some lodge in a toothpick on the switch).
On the pic below you can see the rear of the hazard light switch at the left
The problem is easy to solve. You just need a new hazard light switch. This is however not as easy as you might think. You canīt put in just any switch from the parts-shop as the original item is connected to 8 wires. You need a original switch. Theese can still be bought from BMW, or from Wallothnesch Germany for roughly 40 Euroīs.
On rare occasions they can also be found used on ebay.
Anyway, replacing the faulty switch will do wonders for the rest of the turn signal system on the car, so this is the solution.
I hope i have helped some with this post so they wont do as i did, and spend hours fiddling with fuses, relays, taking half of the instrumentpanel apart etc