Re: emergency flasher switch ?

[John Buchtenkirch]

Well it took the dealer over 2 months to get it for me and I was so involved with rebuilding my bathroom it took me another 3 months to try and install it……. wouldn’t you know it ended up being the wrong switch . My question is are the emergency flasher switches that seem to be so readily available on eBay Asian and should they be avoided ?? Thanks ~ John Buchtenkirch

 

[DougE]

Stays On?

Will your old switch not lock in the off position, is that the problem?

 

[John Buchtenkirch]

Will your old switch not lock in the off position, is that the problem?

Yes thanks, that is my exact problem. The kinda funny part of this story is when I had it out yesterday I realized that leaving off the red lens allows it to lock into the off position :?: so I’ve got a bit of stall time on this repair for now. Leaving the lens off allows the barrel inside the switch to angle causing it to lock in the off position ! ~ John Buchtenkirch

 

[HB Chris]

John,

These switches were changed I believe when the window motors with circuit breakers appeared in early 1973, they cannot be interchanged. The old one can be opened up, I know it helps to have three hands though, and the contact/spring bent back into position. I have done this successfully but it is PITA.

Chris

 

[HB Chris]

Here is an early switch I took apart, it had the same symptoms. The arm you can see needs to bend inwards, it rides in the track of the button. You can also see QC 69 on the cover screw, I have another that says QC 72 for later cars with the resistor.

 

[x_atlas0]

Thankfully the hazard switch itself is not too hard to fix, it just requires several small flat-head screwdrivers to get the main case parts to split. Once you get it open, bending the retaining arm back is very easy.

 

[Luis A.]

Thankfully the hazard switch itself is not too hard to fix, it just requires several small flat-head screwdrivers to get the main case parts to split. Once you get it open, bending the retaining arm back is very easy.

For me the key to opening that style case is to insert a very small flat bladed screwdriver in the seam between the two pieces, under each locking tab, and forcing the plastic up such that it clears the edge of the tab. After you'e done 2-3 tabs the case can be partially split open making the other tabs easier to pry open. Be careful, said small screwdriver can slip off the seam and pierce your finger pretty deep... ask me how I know...

 

[DougE]

Yes thanks, that is my exact problem. The kinda funny part of this story is when I had it out yesterday I realized that leaving off the red lens allows it to lock into the off position :?: so I’ve got a bit of stall time on this repair for now. Leaving the lens off allows the barrel inside the switch to angle causing it to lock in the off position ! ~ John Buchtenkirch

If you'll unscrew the lens that covers the bulb, spray WD40 in the area where bulb plugs in return the lens and then exercise the switch. I've found there is a mechanism in the switch that either needs to be lubed or the WD40 frees it up. This has worked for me on a number of switches.

Doug

 

[John Buchtenkirch]

If you'll unscrew the lens that covers the bulb, spray WD40 in the area where bulb plugs in return the lens and then exercise the switch. I've found there is a mechanism in the switch that either needs to be lubed or the WD40 frees it up. This has worked for me on a number of switches.

Doug

Everyone loves the ease of spray bomb fixes……. too bad they rarely work 100%. Having said that I have to admit that your idea certainly seems to be working :wink: at least for now. Big thanks Doug. ~ John Buchtenkirch

 

[DougE]

I'm not so big into spray fixes but I do prefer the path of least resistance.

 

[Antar]

Thanks guys because of this brief discussion I was able to avoid having to purchase my third hazard switch for my car, although, it would be the third in 23 years I followed the instructions disassembled the switch, bent the capture rod back in place and it works good as new. Have a great weekend of working on or fall coupe driving.

 

[jmackro]

Went to start the car today, and the battery was totally dead. Hooked up the charger and the 4-way flashers started. Having owned a bunch of these cars, I recognized the problem: the emergency flasher switch had given up the ghost. Oh well, at least it happened in my driveway - I remember leaving my old Bavaria at ANZA park at SF airport back in the 90's and having the switch decide to go into flasher mode.

I know you can unscrew the red lens to wedge the button into the "non emergency" position. Or spray WD-40 in there to make it latch a little longer. My worry is that one of those fixes will work for awhile, but eventually will fail again.

Here's what I did do: spent a few minutes with my ohm meter to determine which terminals interconnect with the switch in normal and emergency mode. Turns out, by making a simple jumper and connecting it across terminals 15 and 49 on the connector (and of course, leaving the connector off the switch) I was able to restore turn signal functionality. Yea, my emergency flashers don't work, but I love these quickee fixes that cost pennies.

Of course, I could spend $$$ for a new switch. Anyone have a good source for the early style, 6 terminal switches? Better yet, anyone have a fix that can be implemented with a DPDT switch, a couple of diodes, and a few connectors?

 

[HB Chris]

Jay,

Good thing it's easier to get to on the 2800CS vs. 3.0CS. You can open it up and bend the two prongs outward so they engage in their tracks. Or check with Jim at Mesa.

 

[sfdon]

Never ever pay for a switch at the counter til you have handed the box to the counter guy and asked him to open the box and demo the switch.
Standard scam is to return the bad part as the new one....

 

[Arde]

Jay I have a fix on paper to fix the problem using the original switch. It consists of realizing the problem is mechanical not electrical, so it inverts the role of the two positions. The off position is now out and on is in. The solid state is always energized by the wire that does not go through the ignition. The output of the solid state is now sent to one or the other path using the switch, and two diodes are used to avoid shorting left and right paths galvanically. If you want the button lamp to work a ground has to be wired in. A quick drawing attached, can build it using my old failed switch.

Again the button is most of the time in the mechanically relaxed position, the system is fail safe because if it fails it stays in that position and does not drain the battery.

 

[John S]

New switch?

Of course, I could spend $$$ for a new switch. Anyone have a good source for the early style, 6 terminal switches? Better yet, anyone have a fix that can be implemented with a DPDT switch, a couple of diodes, and a few connectors?

I bought a couple of the 6 terminal switches by mistake for my '73 2002tii. It turns out that my car was built late enough in '73 that it takes the 8 terminal switch. It's brand new from BMW and the seal on the box hasn't even been opened. I paid around $50.00, will sell to you for $25 shipped within the USA. Let me know if you're intersted. Thanks,
John

 

[jmackro]

Jay I have a fix on paper to fix the problem using the original switch. It consists of realizing the problem is mechanical not electrical, so it inverts the role of the two positions. The off position is now out and on is in.

Arde:

I spent some time this morning following my e9 wiring diagrams and taking a continuity tester to my old switch, and came up with a solution that substitutes a cheap, reliable DPDT switch and a couple of diodes for the expensive, trouble-prone factory part. The diodes are used the same way shown in your schematic - they allow one input to power both the L and R lights when the flashers are in "emergency" mode. Admittedly my design only exists on paper, but I am confident it will work.

However, I like your idea better. The switch should last forever if it is only depressed in emergency situations (I hope not to have too many of those!). One thing your design does give up: with the switch wired the "factory" way, the turn signals only work with the ignition switch on. Your circuit always provides unswitched +12 to the flasher, so if you leave the TS lever on with the car parked, the lights will flash until the battery dies.

 

[Arde]

Yep, that is true but my stalk would already kill the battery because in my car it turns on parking lights on one side with ignition off. The flasher is now an audible warning...

 

[jmackro]

Yep, that is true but my stalk would already kill the battery because in my car it turns on parking lights on one side with ignition off. The flasher is now an audible warning...

Yes, good point. Leaving the TS switch engaged is never a good idea. And you're right, having parking lights AND turn signals going is more likely to get your attention.