1993 BMW 318is Hazard/brake lights

Driver side brake light is out and new bulb in place. Passenger and center deck light work. Also, hazard light will not turn off inspite of disconnecting switch. Will only turn off if I remove the relay. Do these stick in blinking mode. Also the ABS waring light is on and cold this be part of the circuit that involves the brake light? This vehicle was unused for over a year but I have found no other real areas of corrosion. Do AutoZone etc carry relays of this sort or do I have to go direct to BMW?



Relay number is BMW 1388533

Just a couple of guesses. That relay could well be bad, but I would also look at all the connectors, as they can become oxidized over time. If you have a combined brake/trun-signal parking light setup try replacing the combination bulbs.

Older e36 BMWs can have several issues with tail lights, all of which are repairable. The fact that the hazard light is acting up may be related to the brake light problem, but I can’t think of how, right off the top of my head.

At the tail light, examine the bulb socket for corrosion or bent contacts. Look through the hole at the contact traces on the tail light housing. Are they bent, corroded, or burned?

Tail lights can be cleaned up. The hardest part is breaking it free from the car as the rubber gasket really sticks to the car after a few years. Remove all the sockets and the nuts and carefully pry it off using at least two pry bars stuck through the holes in the body where the bulb sockets were.

With the tail light assembly off, you can clean the traces and solder closed any holes that may have burnt through the trace. Grind the solder smooth with a dremel tool. I have also cut the plastic plug off, resoldered all the pins to the traces, and epoxied the plug back on when I suspected poor contacts between the plug and the traces.

A dead stop light could be the due to a failed sensor that detects bulb failure. Hopefully not, as that sensor is not cheap.

If you work on your own car a lot, get a Bentley manual for your car. It will have your complete wiring diagram so you can diagnose your problem(s).

The SRS light is probably nothing. Any voltage spike or other electrical irregularity, or just jambing the seat belt buckle together at an odd angle, will set an SRS code on an e36. Borrow a PEAKE SRS tool (or similar), read the code, and reset the light. If the light comes back on immediately, you MAY have a problem with the air bag system. This is not related to your tail light problem.

Thank you Manolito. I did a complete breakdown of the brake light assembly on the side that does not work. It was totally free of any corrison and all the contacts were super clean. Also, the back-up light, the turn signal and the running light all are operative. I noted that the brake pedal switch has 4 leads and can it be that it controls or sends messsages to the right and the left independently?

Of note, in regards to the hazard/turn signal flasher, when I remove it from the power distribution module, the lights turn off and as soon as it is replaced the hazard lights blink, even with the hazard switch removed.

You mentioned a Bentley manual, where are these obtained from and are they any better than say the ‘Mitchell on Demand’ which I access thru the local library?

Thank You again…ggr

The brake pedal switches on e36s are prone to failure and tend to get replaced after 10 years or so. But I don’t think this is your problem. The brake switch has one set of contacts for the brakes and another to turn off the cruise control, hence 4 wires.

Best price I have found for a Bentley manual is on Amazon. I have never tried Mitchel on Demand, but a Bentley manual is better than a paper Mitchell manual for a BMW.

With a wiring diagram and an inexpensive voltmeter, you can check the voltage and ground potential at each pin of the relay and the tail light bulb and track down the problem.

Dear Manolito: I recall a few years back mention of the Bentley manuals when I was on another project and may have seen one. I checked with Amazon as well as ABE.com for used manuals and they run anywhere from 5o to 80 dollars. I went down to our county library here in Toledo and lo an behold they had a BMW #3 manual. You are absolutely right, the detail was profound. Mitchell on demand is ok on the computer but to leaf thru a hard copy of a very detailed manual is almost overwhelming for its detail.

I am awaiting a Wehrle 7-prong black flasher relay for turn signals and hazard lights purchased from BMWPartsWeb.com for 26.71+ 8.00 Fed-Ex. Local BMW dealer cost was 52.

I still have not solved the left brake light out problem and I hope it does not having anything to do with the whole ABS system which is a little too deep for me.

Thanks again for your inputs…ggr