New Bosch ignition switch - 3 connectors

[Andrew77]

Hi,
My ignition switch is broken so I have bought a new Bosch replacement which was recommended to me, however this only has three connectors. Can anyone tell me how to wire this up please, bearing in mind that there are several more wires than connectors. My internet searching has come up with nothing. Many thanks for your help. Andrew

[Jaems]

What are the numbers on the 3 posts? Also what type of car was this one for originally and will the switch have a key turn for the starter. If not then you will have to wire in a button for the starter.

30 is the power (red wires)

50 is for the starter (yellow wire)

75 is for the radio. ( can be hooked up at 30) Red/white wire. You will have to make sure it is turned off even with the key off or out of the car.

57a is for the combination turning signals, high bean, and etc. (white or gray wire).

Otto, I think was a electrical engine. He should be able to help you more on this.

[Andrew77]

Thank you. The numbers on the one are 30, 50 and 15/54 - I think its designed for a VW Beetle really, although I was told it was compatible. Mine is a 1968 and does have a key with an ignition starter, but no parking light position. I am also not sure which is the parking light wire on the original switch. Am I right in thinking that the thicker red wire is power coming in and the thinner one coming out?

I do have a copy of the wiring diagram, however it have more connections and different numbers to the new switch.

Thanks for your help

[Jaems]

The 30 will be the power in. The 50 should be for the starter. The 15/54 is probably for a the radio or ?

If was for a VW. I would ask one the early VW shops what they were (the number posts) were used for. Though I would have preferred you had gotten one for a later 356 or 911/912.

As for the thick red wire, just follow it. If it goes directly to the firewall. Then it is the main power wire from the number one fuse. The other two red wires go to the light switch and combination turn signal and etc. switch on the steering column. The white or gray wire may will work from the 15/54.

However, do be careful when trying the wire on that switch. Since Otto and myself are not there to help you. You can easily burn out some other wiring. If they start to get warm. It is probably good to say they are connected wrong.

[Andrew77]

This one is just a temporary measure as I am hoping to have the original one reconditioned,when I can find someone that can do it, as I would prefer to keep it as original as possible.

I will try what you have suggested - thank you very much for your help, it is much appreciated.

[Cobra06]

Here are the terminal number designations for Bosch, helps when you're wiring.
http://www.bosch-automotive-tradition.com/media/en/automotive_tradition_1/teile_1/switches/downloads_3/klemmenbezeichnungen.pdf

[Andrew77]

Thank you!