yet ANOTHER flasher indicator question

JFENG

JFENG

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Guys, I'm about to head out to get the wiring diagram in my blue binder enlarged by 2x so I can read the damn thing. I have 2 problems that I hope someone can help with
(1) Despite having 2 sets of blue binders, none of the wiring diagrams show the '74 and later setup with the 8 pin E-flasher switch. I'll post on the parts forum to see if someone wants to do a trade

Problem #2: has 2 parts. First, the turn signal blinker only flashes for one side. On the other side I get one flash and nothing. turn lights all blink and the relay makes a consistent and correct speed click/clack. Second, the E-flasher switch doesn't work in that I hear one weird partial click from the flasher relay and no lights blink.

Diagnosis: I've did the standard trouble shooting -
(1) cleaned all contacts and verified consistent resistance for all 4 turn signal bulbs thru the wiring from/to the flasher RELAY connector. This test includes the turn switch, connector plugs, grounds at the lights AND the ground path back thru the body of the car to pin 31 at the flasher relay. The resistance for the 21watt circuits are all about 6 ohm, give or than 0.1 ohms.

(2) I tested my flasher relays on the bench to make sure they all flashed with loads representative of what's in the car.

(3) I even adapted a modern electronic relay (CEC EF26 with a socket/pig-tail) just in case my flasher relays were all bad .

(4) I tried multiple E-flasher switches.

So far, the symptoms remain unchanged. No e-flasher operation and 1-blink turn indicator light (on the speedo) for one side.

Does this means my turn signal switch is bad?

Thanks for any advice.
 
Last edited:
Do you know how to disassemble and clean your emergency flasher button?
Easier than it looks.
 
The 74 model has about 8 ground wires that get loose just to the left of the steering shaft.
10 mm bolt
Open door to fuses/hood latch look up and to right. Grounds are left of steering shaft.
 
sfdon said:
The 74 model has about 8 ground wires that get loose just to the left of the steering shaft.
10 mm bolt
Open door to fuses/hood latch look up and to right. Grounds are left of steering shaft.
Click to expand...

Thanks Don,
symptoms are the same across 3 e-flashers (E9 and late 2002, all 8 pin type).
I will double check the ground point.

I will take apart one of the 2002 EF switches just to have a look inside. Are you suggesting the E9 EF switch might be faulty and cause the 1-blink on 1-side turn signal issue? This is why I want to see a wiring diagram!

It's amazing how many unconnected connectors I found under there. One set is clearly for fog lights, which the car doesn't have. There's another set of 3 that I don't recognized and 1 stray wire that I think is for a seat belt buzzer. Despite being 98% original and untouched, dealing with wiring is still a PITA.
 
Test 1: Bypass the 12V at the flasher switch and see if turn lights work ok now.

Test 2: not needed if test 1 is conclusive.
 
How to test your 6-pin flasher switch

sfdon said:
That's why God made wine....
Click to expand...

Based on the 6 pin flasher switch diagram, here are some simple tests to check the switch operation. With the switch out of the car:

BUTTON IN
(1) short from pin 15 to 49 (power to flasher relay when ignition key is on)
(2) open from pin 49a to both pin L and pin R
(3) open between pins 30 and 49

BUTTON OUT
(1) short from pin 30 to 49 (30 is always hot and this delivers power to the flasher for emergency flashing)
(2) short from pin 49a to both pin L and pin R (connects flasher relay output to light bulbs, bypassing turn signal switch).
(3) open between pins 15 and 49

My flasher switches pass these tests. Not yet sure how to test the red bulb circuit other than verifying the bulb itself is ok (16ohms).
 
The only remaining test that comes to mind would be to unplug the turn signal stalk and see if it affects the emergency flasher operation. Could also swap L and R wiring to the stalk switch and see if the turn signal problem moves sides.
 
I have the BMW Circuit Diagram CD. It shows diagrams for the 74 model.
I bought these when working on a 74 a while back.

With that said I have spent at least and hour trying to figure out a good way to print it out.
I can get reasonable quality 8x10 prints but anything bigger and the quality gets pretty bad. It's in two sections. Front and back of car.
They (BMW) have made it pretty hard to do much more than look at these files on the computer.
It does have a copy write.
I would be glad to print the best I can and mail them to you or anyone else for that matter.
There is also a legend showing what number is what item .
I have not be able to print that at all.
Can only do a screen shot and it would take multiples of those to get the whole legend.
In fact it took 7 times with snipping tool to get all the legend.

Name?

Gary Beck
 
Gary,
Very kind of you.
I'd be happy to get a screen shot of the 8 pin hazard switch.
Just grab the screen, paste it into any image editor and crop down to the switch diagram.
The rest I've already inferred from the 6 pin (I put it into a little chart describing each pin, it's function, wire color, and where the wire goes).

Thanks for the help
John
 
This may be a bust John.

This is how the file is listed on the CD.
BMW 2.5 CS - 3.0 CSi/A, 3.0 CSL (3.15 ltr.) (USA, model 74)

When I actually look at the flasher circuit it does not look like an 8 pin connector for the flasher.
Typically BMW does not get the conversion to English very good.

So I printed 3 different zoom levels of item #42 which the legend says is the flasher. I scanned them and put on Dropbox.

https://www.dropbox.com/s/uhacxixb1th8fdr/E9 74 elec001.pdf?dl=0

Hope this works ok. My file management skills are getting worse instead of better.
Let me know.
Gary
 
I once drew the missing part of the turn signal circuit based on my car's wiring, I can try to find it tonight.

It is not clear if the single blink turn signal fault has the instrument light ON or OFF. If it is OFF it suggests too little load on that circuit I recall.

Is this a US or Euro car?
 
Gary,
Thanks again. With your zoomed in pics, I traced out the in/outs for the hazard switch and relay. Everything looked ok and resistances looked good too. THen I put my voltmeter on the switch pin 30 and it said 12v. Then I went button out and pin 15 said 3volts?! That's the problem. Turns out the fuse, which I had spun around in the clips, was corroded enough that it would show 12v at no current draw but dropped to 3v as soon as the flasher relay tried to pull current from it.

So, e-flasher and turn signals now working fine. Didn't need the electronic 4 prong relay (it's now a spare). But I still have the 1-blink for right turn indicator. I guess I can pass state inspection with that minor fault.

Thanks to everyone else too. The fuse thing is pretty embarrassing. I went back and put contact grease on all the fuse tips. ..

John
 
bfeng said:
Gary,
Thanks again. With your zoomed in pics, I traced out the in/outs for the hazard switch and relay. Everything looked ok and resistances looked good too. THen I put my voltmeter on the switch pin 30 and it said 12v. Then I went button out and pin 15 said 3volts?! That's the problem. Turns out the fuse, which I had spun around in the clips, was corroded enough that it would show 12v at no current draw but dropped to 3v as soon as the flasher relay tried to pull current from it.

So, e-flasher and turn signals now working fine. Didn't need the electronic 4 prong relay (it's now a spare). But I still have the 1-blink for right turn indicator. I guess I can pass state inspection with that minor fault.

Thanks to everyone else too. The fuse thing is pretty embarrassing. I went back and put contact grease on all the fuse tips. ..

John
Click to expand...

That's great John.
Glad you figured it out. Yes those fuses can "get" you.

Happy Thanksgiving.
 
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