Front Sidemarker Flasher Module Options

[Spoke]

Maybe this is the procedure in this thread:
https://forums.pelicanparts.com/porsche-914...rn-signals.html

@FlacaProductions

(IMG:style_emoticons/default/agree.gif)

This looks like the mod to make the sidemarkers flash with the turnsignals. Although it only works if all bulbs are incandescent.

This is a simplified schematic of the OEM front turnsignal, front sidemarker and rear turnsignal. Front sidemarker is independent of the turnsignal.



In the modified solution to blink the sidemarker, the sidemarker ground wire is removed and that pin of the sidemarker is attached to the turnsignal wire.

With running lights off and turnsignal active, the turnsignal input alternates between 12V and zero thus powering the sidemarker through the front and rear running light filaments to ground. The front and rear running light filaments are 5W each while the sidemarker is probably 2-3W. Most of the 12V is dropped across the sidemarker.

With running lights on and turnsignal active, the sidemarker is off when the turnsignal is on and sidemarker on when the turnsignal is off.

This is the same principle behind the foglight relay and high beam headlight. Works well with incandescent but does not work for any LEDs in the circuit.

[FlacaProductions]

Interesting and didn't want to rain on your development parade - but since that mod is only for incandescent bulb, i'm out. LED all the way....eagerly awaiting your boards.

[Spoke]

The driver side installation went very well. Lessons learned from the passenger side disassembly and reassembly made installation much easier.

After pulling the connectors off the turnsignal and sidemarker, the sidemarker boot was warmed up and with soapy water, the 2 connectors were pulled out without breaking.

To unfish the wires from the turnsignal boot, the end of the boot going to the trunk was pulled out which made finding each wire and pulling them out of the boot much easier.

On reinstall of the sidemarker boot, instead of pre-crimping the spades on the sidemarker wire then trying to fish them in, the wires were fished into the turnsignal boot then sidemarker boot and spades crimped on then.



With both boots free of the vehicle, it was simple to fish the new wires into the boots then mount the boots on the vehicle.

[fixer34]

So I got looking at the diagrams and wondering if this will work. Need 2 small relays and 2 diodes. Should be able to mount on a small PCB.

Turn signal feeds thru N/C contact on TR relay, diode prevents backfeed to running lights.
Running light likewise feeds thru RR relay. Also energizes TR relay
When running lights on, and turn signal activated, Flasher pulses the running lights relay, effectively turning them off. So the side marker actually flashes opposite of the front and rear lights.
Minimal stock wiring disruption and should work for incandescent, LED, or a combination.

 Relay_board.pdf ( 1004.76k ) Number of downloads: 40

[Spoke]

So I got looking at the diagrams and wondering if this will work. Need 2 small relays and 2 diodes. Should be able to mount on a small PCB.

Turn signal feeds thru N/C contact on TR relay, diode prevents backfeed to running lights.
Running light likewise feeds thru RR relay. Also energizes TR relay
When running lights on, and turn signal activated, Flasher pulses the running lights relay, effectively turning them off. So the side marker actually flashes opposite of the front and rear lights.
Minimal stock wiring disruption and should work for incandescent, LED, or a combination.

 Relay_board.pdf ( 1004.76k ) Number of downloads: 40

Looks like a cool circuit. Pretty much what I'm doing. I have the steering diodes and instead of relays I'm using FETs although I only have one FET. The FET is controlled by a comparator circuit which monitors the turnsignal and turns the FET off.

The PCB is turning out to be a small part of this assembly. Between having 30 individual wires and 40 spade crimp connectors, assembly of the wires is the most intense process.

[fixer34]

So I got looking at the diagrams and wondering if this will work. Need 2 small relays and 2 diodes. Should be able to mount on a small PCB.

Turn signal feeds thru N/C contact on TR relay, diode prevents backfeed to running lights.
Running light likewise feeds thru RR relay. Also energizes TR relay
When running lights on, and turn signal activated, Flasher pulses the running lights relay, effectively turning them off. So the side marker actually flashes opposite of the front and rear lights.
Minimal stock wiring disruption and should work for incandescent, LED, or a combination.

 Relay_board.pdf ( 1004.76k ) Number of downloads: 40

Looks like a cool circuit. Pretty much what I'm doing. I have the steering diodes and instead of relays I'm using FETs although I only have one FET. The FET is controlled by a comparator circuit which monitors the turnsignal and turns the FET off.

The PCB is turning out to be a small part of this assembly. Between having 30 individual wires and 40 spade crimp connectors, assembly of the wires is the most intense process.

Yea, I figured there was a way to do it with modern electronics, I just went 'old school' to see if it would work.
A lot easier to draw out on paper than to integrate into an actual wiring harness.

[BillC]

@Spoke -- I love the idea, but have a question about the installation. Instead of installing two modules, one at each front corner, what about making a single module that goes under the dash and connects to the switch end(s) of the wiring harness? This seems like it would be a simpler install, since you wouldn't need to pull the wires out of the fenders and rubber conduits/boots, and you could control both sidemarker lights from one box. Basically, it would be putting the new controls at the other end of the wires, instead of at the light-bulb end.

[Spoke]

@Spoke -- I love the idea, but have a question about the installation. Instead of installing two modules, one at each front corner, what about making a single module that goes under the dash and connects to the switch end(s) of the wiring harness? This seems like it would be a simpler install, since you wouldn't need to pull the wires out of the fenders and rubber conduits/boots, and you could control both sidemarker lights from one box. Basically, it would be putting the new controls at the other end of the wires, instead of at the light-bulb end.

@BillC

Interesting idea. Not sure where the wires would be under the dash or maybe on the fuse panel.

On my '71, the passenger side had 4 wires: turnsignal, running, sidemarker, ground. On the driver side there were only 3 wires: turnsignal, running+sidemarker, ground. So not sure the wires for both front sidemarkers could be found on the fuse panel.

[fixer34]

@Spoke -- I love the idea, but have a question about the installation. Instead of installing two modules, one at each front corner, what about making a single module that goes under the dash and connects to the switch end(s) of the wiring harness? This seems like it would be a simpler install, since you wouldn't need to pull the wires out of the fenders and rubber conduits/boots, and you could control both sidemarker lights from one box. Basically, it would be putting the new controls at the other end of the wires, instead of at the light-bulb end.

I believe the sidemarkers are connected to the front running lights on each side with just a couple 12" (guess) wires, 12v and ground. To have them work independently from the front signals, you would need to disconnect the short 12v ones and run at least 1 wire from under the dash along the existing harness up to each side marker. So you are into the conduits/boots anyway.
In theory there would be less wiring modification since you 'should' be able to add the inputs to the control board right from the source switch as you say. The turn signal/flasher connection is actually quite easy; add spade lugs to fuses 5 and 6 and those are your left/right inputs. Running lights/emergency flasher is another matter. those wires come directly off the flasher. A bit of work to get to that and add a spade lug to the switch, then run that wire down to the control board.
Would require a 'dual' control board since flashing each sidemarker is an independent operation.
Both options would work, one isn't necessarily better/easier than the other. Just depends where you want to put your efforts.

[BillC]

@Spoke -- I love the idea, but have a question about the installation. Instead of installing two modules, one at each front corner, what about making a single module that goes under the dash and connects to the switch end(s) of the wiring harness? This seems like it would be a simpler install, since you wouldn't need to pull the wires out of the fenders and rubber conduits/boots, and you could control both sidemarker lights from one box. Basically, it would be putting the new controls at the other end of the wires, instead of at the light-bulb end.

@BillC

Interesting idea. Not sure where the wires would be under the dash or maybe on the fuse panel.

On my '71, the passenger side had 4 wires: turnsignal, running, sidemarker, ground. On the driver side there were only 3 wires: turnsignal, running+sidemarker, ground. So not sure the wires for both front sidemarkers could be found on the fuse panel.

Oh well, it was a nice idea while it lasted. Once again, outsmarted by those old german engineers.... (IMG:style_emoticons/default/headbang.gif)

Any idea when these new modules will come to market? I'll want to buy a set when I order the front LED boards (already have the rear boards).