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  View original topic: Push Button Start decyphering
airkooledchris Fri Jun 09, 2017 6:17 pm

I recently had smoke rolling out from behind the dash and now it's time to try and clean up all of the PO's mods to how things work.

There is a push button starter installed.
The push button starter has two wires connected to it.
1 - splices into a large gauge solid red wire that connects to the #9 accessory fuse (which also had a piggyback connection with the #30 spade off of the headlight switch.)




2 - splices into a large gauge sold red wire with black stripes coming out of the ignition switch, before it leads into a factory connector mounted to the underside of the flat metal plate behind the dash where the steering column is mounted.




I used to think it was just those two wires and that was it, but I found a relay in this setup.

The relay is marked 1,2,3,4,5, although the #2 is blank:


4 - this wire splices into the large gauge solid red wire with black stripe, after it leaves the connector under the dash and before it (im assuming) heads back to the starter. 
5 - this wire is connected directly to fuse #10, which is usually just for the wipers and rear window defogger.


I did try going back to a normal setup previously by fixing the ignition switch, but that failed 6 months later so I do want to keep the push button setup, but I need to clean this up. I don't understand what the relay is doing or why it's there. I have some decent 10G wire I can use to replace those freakin brown lamp cord wires that were used before, but should I splice it right back to where it was before?


The whole reason this project started is a wire shorted out behind the dash and started smoking. The brown wire on the #30 spade of the headlight switch grounded onto the back of the instrument cluster. This brown wire connected to spade #30 on the headlight switch was connected to the same #9 fuse with the large gauge solid red wire. I replaced the brown wire from the #30 spade to the #9 fuse, but onto it's own blade on the #9 fuse - separate now from the large gauge solid red wire.

If I could get a RELIABLE damned ignition switch id love to ditch all this crap and just set it back to where it should be, but at this point I don't know where that would even be. When I did put in a replacement switch I never disconnected any of the pushbutton stuff, it just worked for a while - in addition to the push button and then eventually failed.

Abscate Fri Jun 09, 2017 7:30 pm

The zip,cord has to come out completely and those solder splices need to be redone too. This is for fire safety, not function

Electrical stuff requires both knowledge ( what goes where) and understanding of good practices. This takes time to learn, it's not in Wikipedia

Don Caseys Boat wiring book is a great place to learn as boat wiring is even more severe than cars

Tcash Fri Jun 09, 2017 8:46 pm

The relay was probably an old work around for the bad ignition switch.
1. Disconnect the battery ground cable.
2. Remove the Relay and the wires that go to it.

The push button is wired correctly.
Although there is no Red wires on fuse #9.
Note the red wires are on fuse S8 [#8]
click on pic


Here is the fuse lay out for 1979. Use the wiring diagram and this to straighten out the fuse box.


Reconnect the battery.

Good luck
Tcash

ps put some liquid tape on those soldered wires or they could short out.

telford dorr Fri Jun 09, 2017 11:14 pm

airkooledchris wrote: The whole reason this project started is a wire shorted out behind the dash and started smoking. The brown wire on the #30 spade of the headlight switch grounded onto the back of the instrument cluster.
Yup - that'll do it! Note that brown is reserved for wires which connect to ground. Thus there should never be a brown wire connected to any terminal 30 (a terminal number always reserved for unfused 12 volt battery power.)

Other reserved colors: black = switched 12 volt power, red = unswitched 12 volt power.

Other reserved terminal numbers: 15 = switched power, 31 = ground

Actually, all terminal numbers have a specific meaning and are generally unique. There's method to the madness...

Quote: This brown wire connected to spade #30 on the headlight switch was connected to the same #9 fuse with the large gauge solid red wire. I replaced the brown wire from the #30 spade to the #9 fuse, but onto it's own blade on the #9 fuse - separate now from the large gauge solid red wire.
Not clear what the PO was doing. Fuse #9 is a spare fuse. It should be bus-bar'ed to fuse 8, which are both fed from a large red/white feeder bringing power from the starter. There should be large red wires from the power side of these fuses to the ignition switch, headlight switch, and fuse 7. ALL of these wires are unfused power, only providing 12 volts to the fuses and switches.

Quote: If I could get a RELIABLE damned ignition switch i'd love to ditch all this crap and just set it back to where it should be, but at this point I don't know where that would even be. When I did put in a replacement switch I never disconnected any of the pushbutton stuff, it just worked for a while - in addition to the push button and then eventually failed.
I would pursue installing a new ignition switch. If it's made in china, forget it. German would be the best. Everything else is cut-and-try.

If you're going to keep the pushbutton, I'd:
- unplug the red/black wire from the ignition switch going to in-line connector T8 and insulate it.
- using the proper terminal on a wire, connect T8 to one side of the pushbutton.
- connect the other side of the pushbutton to a wire with a piggyback terminal on it to a terminal on the power side of fuse S8 or S9, replugging any unplugged wire onto the piggyback terminal.
This way, when you eventually replace the ignition switch, the pushbutton can be easily removed from the system.

[Clarification: all fuses have a "power" side and a "load" side. Raw power feeds the "power" side of a fuse. The load the fuse protects connects to the "load" side of the fuse. Generally, all of the lower sides of fuses in the fuse block are the power side and the upper side of the fuses are the load side. Also: only red (16 amp) and white (8 amp) fuses are used in VW's. Any other color - specifically blue (25 amp) - should never be used.]

airkooledchris Sat Jun 10, 2017 10:36 pm

telford dorr wrote:
I would pursue installing a new ignition switch. If it's made in china, forget it. German would be the best. Everything else is cut-and-try.

If you're going to keep the pushbutton, I'd:
- unplug the red/black wire from the ignition switch going to in-line connector T8 and insulate it.
- using the proper terminal on a wire, connect T8 to one side of the pushbutton.
- connect the other side of the pushbutton to a wire with a piggyback terminal on it to a terminal on the power side of fuse S8 or S9, replugging any unplugged wire onto the piggyback terminal.
This way, when you eventually replace the ignition switch, the pushbutton can be easily removed from the system.

Thanks, it works and it wasn't too difficult really. I get what their thought was with the relay, but it wasn't setup properly to do what they thought.

I'll try throwing yet another ignition switch at it and see what happens. I think I went with German last time around, but it's possible they weren't available at the time and I rolled the dice. It's been a few years since then, maybe there's good options again.



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