Understanding the Emergency Flasher Switch
 

On my 1985...

The switch is a standard Hella 001579-09 which is today available as a 001579-11.

http://forums.pelicanparts.com/uploa...1427239114.jpg

http://forums.pelicanparts.com/uploa...1427239194.jpg

It has a mating connector attached to a short wiring loom. That loom is Porsche specific part number 911 612 014 31 I believe.

Once the loom is separated from the switch you can read the contact designations (from the top clockwise):

http://forums.pelicanparts.com/uploa...1427239255.jpg

30 - power in from always hot bus; a single red/black wire going through the connector on the front bulkehead to fusebox 1 fuse 2.

49a - two wires - one black/white/green going to the turn signal/headlight dim switch, and another black/white/green through the connector on the front bulkhead to position 49a on the turn signal relay.

49 - a single red/white going through the connector on the front bulkhead to position 49 on the turn signal relay.

58 - a single wire listed as brown (but mine is white) with diode P/N 911.612.249.00 connecting through a single pin connector to the headlight switch position 58a.

31 - a single brown wire with faston connector going to local ground.

L - power out to the left side lights; a single black/white wire going the bulkhead connector.

15 - power in from the hot in start and run bus; a single green/red wire going through the connector on the front bulkhead to fusebox 1 fuse 8.

R - power out to the right side lights; a single black/green wire going the bulkhead connector.

The switch has a key molded into it to insure proper orientation during connection; you can see that near position L.

The loom connector simply pushes onto the switch once the key is aligned.

To remove the switch from the car, disconnect the loom from the switch and from behind the dash, squeeze the two plastic ears, and pull the switch through the front of the dash.

Nice write up! How is the dash coming along?

Hey Jeff,

I am done with the removal of systems and backdating the heat, relocating the battery and created new wiring scheme. I am finally hooking up wires now to the new fuse box. After that, I will get the car running and drive it to access the steering and brakes (since it has been a while). Then I will take it down again to deal with that and suspension. The interior makeover (dash included) will be down the list. Oh what a can of worms I opened...

Mike

Great info. Thanks!!

Whoa, do not buy a replacement switch using the part number I suggested until reading this post. I ordered the Hella P/N 001579-11 through Amazon Prime for $38 thinking that was a pretty good deal. Here is the Hella page for it:

Hella HD :: Hazard Flasher Switch

I got the box today and it is Hella original, but it is a box of 5!

Sure enough they list bulk qty = 5 for that part number. There is no part number for a single item.

http://forums.pelicanparts.com/uploa...1427492024.jpg

http://forums.pelicanparts.com/uploa...1427492074.jpg

The differences:

The original has the clearer plastic and the new is black.
The original says "Made in Germany". The new says "Made in India".
The front red push button has a different icon on it, but this part just screws off so that you can access the bulb from the front. You can place your old on on the new switch if you want.

Both switches feel the same and mate up to the loom the same.

http://forums.pelicanparts.com/uploa...1427492300.jpg

http://forums.pelicanparts.com/uploa...1427492323.jpg

I will be testing it in the next two weeks when I finish my electrical redo.

Mike

PS if anyone wants one, let me know. I will make you a smoking deal.

Subscribed. Thanks for sharing your expertise Mike.

Henry

My pleasure!

Just as an added bit of info...the new switches I bought DO NOT come with bulbs. I used the one from my old switch. It is labeled OSRAM 12V 2W. I am not sure of the size.

Okay, finally wired it up and and promptly blew a fuse. Looking at the terminal designations on the new vs old it looks like Hella may have switched a power and ground. I see that what was terminal 31 (ground) is now terminal 30b (power?) and what was terminal 58 (to the lights) is now 31 (ground). Interesting.

There were two folks that bought new switches from me...please follow this as I try to solve this one.

Here is the schematic from Hella for the new switch:

http://forums.pelicanparts.com/uploa...1446066757.jpg

Comparing old and new schematics it looks like socket wire 31 needs to be relocated to position 58 according to old switch designations (or 30b switched to 31 according to the new switch designations), then wire 49 need to be jumpered with 30b according to the new switch designations.

Lastly, the wire with diode going to position 58 (old designation) is no longer needed. Cap and stow this one. This wire looks like it lit the switch when the headlight switch was pulled out.

Mike

Here is the Emergency Flasher circuit for the SC and Carrera years:

http://forums.pelicanparts.com/uploa...1446065748.jpg

Note the difference is the switching between busses 15 and 30 that power the relay through connection 49. In the "old" circuit the switch toggles between 30 - always hot bus and 15 - hot in start and run.

Contact 58 powers the light on the switch from the light switch through a "resistor" it seems.

On the "new" switch, the power from 15 is switched on or off to contact 49 but power from 30 to 49 is not available regardless of switch position. That is why I had to jumper 30b and 49. Then I moved the ground wire to the correct location labeled 31 on the "new" switch (position 58) of the "old" switch. It seems to work now.

Putting both switches side by side in similar schematics:

Old:
http://forums.pelicanparts.com/uploa...1446066535.jpg

New:
http://forums.pelicanparts.com/uploa...1446066757.jpg

I did the two simple wiring mods above and the switch works.

Hi Mike,

I saw this thread a while back and committed its existence (although not its valuable details) to memory for future reference. The reason is I've deleted the center console but found that the turn signals won't work without the flasher switch connected. And I've replaced my dash with the Rennline version so would like to incorporate a simple two-pole (with ground) aftermarket toggle switch for the flasher because the plastic ears are broken on my stock flasher.

I'm not as knowledgeable as you are about electrical wiring so excuse my ignorance, but could I just separate the wires bringing power to the factory switch (30, 15) from the wires leading to the relay, turn signal lights, and indicator lights (49, 49a, 58, L, R) and use a two pole grounded switch like this one?

http://forums.pelicanparts.com/uploa...1479079333.jpg

TIA for any advice you can offer.

Jeff

Subscribed. Would love to see this as well.

Here is my take for when the EFS is engaged:

http://forums.pelicanparts.com/uploa...1479141895.jpg

When the car is not running, the flashers will work because power is available from terminal 30 (always hot bus). When the Emergency Flasher Switch (EFS) is pushed in, power is then taken from terminal 30, and all of the outputs L, R, and 49a are ganged together and powered by the flasher. When you activate the EFS the red current flow is in play. Power comes in from terminal 30, powers the flasher relay, which in turn powers the left side lights of the car, the right side lights of the car and the two turn signal lights in the dash.

The orange path to the left its the power to light the bulb in the EFS when the headlight switch is turned on so that you can find the switch at night.

When the EFS switch is not engaged, then power from terminal 15 (when the car is in start or run key position), power goes to through the flasher relay, but the outputs are not ganged. Power goes to terminals 49a and into the light switch to only power the car lights and gauge lights on one side of the car.

I think you could replace this switch with a simple setup, but not with a single pole single throw switch. To use that switch you would give up functionality (like allowing the turn signals to work).

To maintain the functionality, you would need at least a double pole double throw switch I would think. The switch would energize the relay from terminals 15 and 30, and you would not have any EFS light to worry about.

http://forums.pelicanparts.com/uploa...1479142566.jpg

The outputs of the flasher relay 49a, L and R would need to be ganged together through one terminal of the switch. The power feed from the headlight switch and the ground from terminal 31 would need to capped and stowed.

Does this make sense?

By the way, this would be current flow without EFS engaged:

http://forums.pelicanparts.com/uploa...1479144191.jpg

This would seem to replicate the switching in the EFS for all but the EFS light:

See below...original sketch removed to prevent mistakes...

Excellent! Thanks Mike :)

I would definitely get a second opinion. Hang on, I see errors in my ways....the flasher is not getting energized this way.

This is more like it I think...still suggest someone more knowledgeable checking this before implementing.

http://forums.pelicanparts.com/uploa...1479149604.jpg

I won't have time to test this out for a week or two but when I do, I'll report back here.

Thanks, Mike. I appreciate your responses.

Jeff

My pleasure Jeff. I may have another new Hella replacement as described at the beginning of this thread. I was sending them to people for the cost of the switch and shipping ( about $15 total) until my original order of 5 ran out. It just requires one wire jumper to function properly in our cars (see thread details). If you are interested, then let me know and I will arrange to go to my hangar storage and search them out.

Mike

Sure, I guess it can't hurt to have it in the event we're unable to figure out how to convert the wiring to a toggle switch. Please PM me your Paypal info and I'll transfer the money to you. Thanks.

I will see if I have any left first - it may be a week or two if I need to head to the hangar.

I spent a couple hours on this over the holiday.

I used a DPDT - On / On switch. This switch has 6 poles with numbers 2 and 5 being common between the top and bottom halves.

In the configuration above, the hazards work as expected.
- Wire 30 (Constant power) energizes Wire 49 (Turn Signal Relay)
- Wire 49a (Turn Signal Contact) is ganged together with the L and R Lights

However, in the other switch position, the turn signal doesn't work properly - both L and R side lights come on when the stalk is flipped in either direction. This is due to having the L and R wires connected together at the switch.

The only two wires needed for the Turn Signals to work properly are 15 (Key Start Power) and 49 (Turn Signal Relay). But when you connect the L and R wires together on the same switch terminal in order to operate the hazard setting, then you will always get both right and left side lights blinking when you activate the turn signal stalk.

I tried multiple configurations on the switch but I was never able to get both features working at the same time.

I am going to attempt to get an 8 pole On / On switch to see if I can get this to work.

That makes sense...thanks for trying and correcting it.

Yes, thanks. Still hoping I can add an aftermarket switch to my Rennline dash. I looked at my stock switch this afternoon and the difference between the switch diameter and the switch face is not that great, meaning if I decide to use the stock switch I have to be very careful not to drill too large of a hole. Fingers crossed that the 8 pole switch works.

Okay, so this is more like it based on OffCamber00's experimentation:
http://forums.pelicanparts.com/uploa...1480287733.jpg

49a connects to L + R ONLY when the switch is engaged. They are isolated otherwise and the normal turn signal switching is active. Good catch.

Mat, any progress or update? Thanks,

Jeff

As a matter of fact, I finally got my 3PDT switch today. Little bugger was hard to find.

I'll mess with it this weekend and post an update.

Hey Mat, any luck yet? Come on, man, I'm counting on you since you obviously understand electrical wiring far better than I do! (shameless groveling intentional) SmileWavy Did I mention I was born in Charlotte?

Gents - sorry for the delay. I was able to get the switch working in the configuration SpyderMike diagrammed out above.

I ended up buying 3 switches since they were a b!tch to find online - if anyone wants one, send me a PM.

mat

I did this and it works perfectly
in fact I like the look of the toggle switch better than the flasher
had and extra thru body plug, wired the toggle direct

Understanding the Emergency Flasher Switch
 

Never mind… answered my own question.

Great write up Michael. I just replaced my flasher harness. New turn signal and i don’t remember a diode. My emergency flasher works, but my turn signals are not. What’s the role of the diode here?
Thanks

Rex

It looks like 58 lights the switch when the headlight switch is activated. A diode prevents reverse current...so the switch does not light up in other conditions...only when the switch is activated...most likely. I see my Haynes manual describes this as a "resistor"...that would most likely just dim the light in the switch.

You say you have a new harness...is the EF switch an old one or a new one?

From post 15, this is how the turn signal are power without the EFS engaged:

New harness. Almost all of them.
New flasher switch
New flasher harness
New turn signal switch
Old headlight switch

Hmmm...On the above diagram focus on Turn Signal Contact (Switch). When the Emergency Flasher is not engaged, the current flows following the green path.

When the EF is engaged, the current can bypass the Turn Signal Switch via L and R terminals and the power comes from a different fuse 17 through terminal 30 on the EF. Check the wire at pin 30 on the EF Switch to see if there is voltage there.

If there is voltage there then I would tend to shift focus downstream...is the voltage at 49a on the Turn Signal Switch?

I haven’t had a chance to chase why I'm not getting power, but i did jump 12V (switch side)to the green/black/white coming from the flasher to the turn signal switch. Flasher still not working with the switch, but i was able to get the left/right front/back lights to follow switch position to lite. I guess this is progress in trouble shooting.

Side note. I did learn my headlight switch has 1 set of male spades that are perpendicular to the switch housing and pics from the form are showing 2 sets of double male spades positioned perpendicular to the housing.

My ignition switch was modified to remove the steering lock (cut/grind/lock delete)

If you bypass the flasher relay, the lights will not flash. That is the purpose of that relay. Bypassing the relay and seeing lights work means that downstream path works.

See if you have 12VDC at 49 on the relay, if you can. If it IS there and yet noting is coming out when you turn signal, then you are down to 49a run between the relay and the EF Switch or the Turn Signal Relay itself, most likely. If 12VDC isn't at 49 at the relay, then you work upstream from there.