New Hazard Switch Electrical Issue

teahead

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Sorry, have to ask. You sure the connector and switch are clocked correctly? Pins going into the right sockets?
 

bavbob

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Good thought. I know this is one place BMW did not make the set-up intuitive....like the crankshaft position sensors on my 635 that I reversed.
 
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HB Chris

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It only fits one way
85A03C30-2CF7-456C-BC61-49B206EAE205.jpeg
 

bavbob

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Are we thinking of the defrost switch? One of them on my E3 can fit a multitude of ways.
 

Arde

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Well, that would be great. I’ll try anything. I’ve been going through all wires looking for ground issues and everything looks solid so far.
Ok, no more shortcuts, here is how to check the switch, based on part #43 of this schematic:

Switch not installed:
PIn # Switch not depressed. / Switch depressed
30 no continuity to any other pin / continuity to pin 49
15 continuity to pin 49 / no continuity to any other pin
L. no continuity to any other pin. / continuity to pin R and 49a
R. no continuity to any other pin. / continuity to pin L and 49a
49a. no continuity to any other pin. / continuity to pin R and L
Light bulb not connected / connected between pins 30 and 49a

Switch installed:
PIn # Switch not depressed. / Switch depressed
30 12V / 12V
15 12V with key in contact, else 0V / 12V with key in contact, else 0V
L. 0V / 12V flashing
R. 0V / 12V flashing
49. 12V with key in contact, else 0V / 12V
49a. 12V flashing / 12V flashing
Light bulb off / flashes

My recollection is that the switch bulb illuminates as the opposite of the markers. When the markers illuminate
there is 12V on both sides of the bulb and the bulb is off, when the marker is off one side of the bulb is 12V and the other is the marker bulbs, so if at least one marker bulb works the light will illuminate.

All the above assume the flasher unit #44 works.

There, all you need is a multimeter, 15 minutes, and a beer.
 

jbrubaker001

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Ok, so results aren’t looking good or I don’t know what I’m doing. I have my multimeter set to test continuity (OPEN means cicuit is not continuous and SHORT means circuit is continue or shorted) - results when NOT installed and NOT depressed (exceptions only) respective top to bottom above:
- 15 to 49 - NO continuity
- L continuity to 49A, R and 31
- R continuity to 49A, L and 31
- 49A continuity to L, R and 31

Results NOT installed and depressed (exceptions only) respective top to bottom above:
- 30 to 49 - NO continuity
- L NO continuity to any other pin
- R NO continuity to any other pin
- 49A NO continuity to any other pin

I am now assuming the notes above from Arde are reversed? If so, the only real exceptions are the 15 to 49 and 30 to 49 - so is pin 49 the issue and if so, what does pin 49 do? Looking at the schematic I can see where 15 is connected/disconnected to 49 but not how 49 connects to 30.

Thoughts?

John
 

Arde

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Ok, so results aren’t looking good or I don’t know what I’m doing. I have my multimeter set to test continuity (OPEN means cicuit is not continuous and SHORT means circuit is continue or shorted) - results when NOT installed and NOT depressed (exceptions only) respective top to bottom above:
- 15 to 49 - NO continuity
- L continuity to 49A, R and 31
- R continuity to 49A, L and 31
- 49A continuity to L, R and 31

Results NOT installed and depressed (exceptions only) respective top to bottom above:
- 30 to 49 - NO continuity
- L NO continuity to any other pin
- R NO continuity to any other pin
- 49A NO continuity to any other pin

I am now assuming the notes above from Arde are reversed? If so, the only real exceptions are the 15 to 49 and 30 to 49 - so is pin 49 the issue and if so, what does pin 49 do? Looking at the schematic I can see where 15 is connected/disconnected to 49 but not how 49 connects to 30.

Thoughts?

John
Yes, that suggests reversing the interpretation of "depressed". I think to activate the hazards you press and the switch mechanically is pulled out, so you would call that depressed....

The problem I see is no continuity to pin 49 in any condition, which is what carries 12V to the flasher.
In other words, the switch is bad, which is the best possible outcome, no need to mess up with wiring, grounds, etc. Just get a new switch.

Time to open it up, maybe the internal connection to the pin broke?
You can always wire 12V to 49 and see if flashers come alive.

BTW, my cheatsheet deals with 6 of the 8 pins, the others (P85, 58D) are irrelevant, including the resistor pin.
 
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jbrubaker001

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Thanks for the reply. Rather than opening up, I have requested a replacement from Pelican. Once I have a new one, I will update this thread. Thanks to all for their support.

Finally - does anyone think the fact that the brake lights still do not work have anything to do with this hazard switch issue?

John
 

HB Chris

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Thanks for the reply. Rather than opening up, I have requested a replacement from Pelican. Once I have a new one, I will update this thread. Thanks to all for their support.

Finally - does anyone think the fact that the brake lights still do not work have anything to do with this hazard switch issue?

John
The brake light is not part of the hazard circuit which uses turn signals. Have you checked the switch above the brake pedal? When switch is released the circuit is completed, you can make sure you have power to that switch.
 

jbrubaker001

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Brake Switch testing results:

- tested the positive wire unconnected - it is hot
- plugged the positive wire into the brake switch - then checked for voltage from the non connected terminal of the brake switch - both depressed and pressed noting no voltage.

I would have expected with the plunger pressed in, the circuit would have been complete and would have picked up 12v from my multitester. If this did not happen, can I now deduce that the switch is bad?

I also checked continuity of the switch both pressed and depressed - only received open circuit results. Again, does this confirm that switch is bad?

All help is greatly appreciated,

John
 

Arde

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I also checked continuity of the switch both pressed and depressed - only received open circuit results. Again, does this confirm that switch is bad?

All help is greatly appreciated,

John

Yes, a switch with no continuity when depressed is a bad switch.
May I suggest another person purchases switches for you, you may have bad Juju for switches :).
 

jmackro

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Ok, so I completed the new flasher upgrade. Still no flashers, no brake lights and new hazard switch does not light up. Does anyone have any insights on where to start testing?
Yes, I'm not surprised. If your old mechanical flasher worked with your old switch, then the electronic flasher wasn't likely to make a difference. Still, the e-flasher is a worthwhile upgrade.

jbrubaker001 said:
Is it coincidence that the hazard and turn signals do not work or is this a bad hazard relay?

I wish I had seen this thread earlier. No, it makes perfect sense that a bad emergency switch would cause both the hazards and turn signals to not work. As Arde wrote in post #10, the turn signal circuit runs through the emergency switch. That's why the turn signals don't work when the emergency switch is disconnected - or when it's bad.

Mot27cars said:
What about if someone sent you an old one and see if it changes things.

I like that suggestion. Evidence sure points to that new switch, since everything was working fine, but it all turned to ___ after you replaced the switch.
 
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Arde

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Doesn’t pushing on pedal close the switch? Normally it is depressed and open.
Yes, I should have used switch ON and OFF positions instead of pressed and de-pressed...
Pressed and de-pressed are more suitable for toggle switches, where the action is always pressing.
 

jbrubaker001

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Yes, it appears that I am having some bad electrical juju. I contacted Pelican about a defect return for the hazard switch and I think they will help me out.
 

jbrubaker001

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Yay! I received my new hazard switch from Pelican today. Tested it as noted above before putting in and everything worked. I plugged it in, pressed in the butto….it lit up and my new flashers worked as expected. Thanks to everyone for all of their help! Also, prior to receiving the hazard, I pulled the brake light switch noting the plunger was defective. Went to my local NAPA store, picked up a replacement and my brake lights work as well. This is how it’s supposed to go!

So excited and thanks again everyone!
 
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