It's been a while since I posted here, but figured I would run this one past the group. My 1970 Series II XKE coupe is having a problem with the ignition switch. The key works fine, but almost every time I take it out these days, the car will just die on me. It's as if I turned the ignition off. I pull to the side of the road, turn off the ignition, fiddle with the wires behind the switch, and eventually I can get the car started again. I've checked the wires, and none seems loose. I have not been able to find a replacement for the electrical part of the switch as it is aparently now longer available. I did take it out about 2 years ago and open it up and clean it up as best I could, but it keeps playing up on me.

Now, I spoke with George Camp about this problem, and George suggested getting the electrical portion for a Series III E-type and splicing the wires into the wiring harness that is build into the Series III switch. So, here's the questions:

Has anyone done this? If so, do you have by chance a wiring diagram showing which leads from the harness on the Series III switch go to which wires on the Series II? Any pictures?

How did you actually make the connections? Did you butt them together, or use male/female connectors?

Any other alternatives to fixing this problem, seeing as there is no source for the Series II electrical switch?

thanks,
Steve Weinstein

Submitted by Anonymous (not verified) on Fri, 03/24/2017 - 22:34

The ignition key on my 1970 E-Type will not automatically return to the 'run' position once I let go of it after the engine starts. Is it the front half of the switch assembly or the back half with the electrical contacts that has the return spring in it? Thanks

Submitted by rlich8@me.com on Thu, 01/06/2011 - 10:11

Edited on 2011-01-06 10:13:08

Martin Robey in the UK has original, NOS switches in stock. I purchased one for my car when I was in England in March and it's one of the best purchases I've made thus far.

Originally my car had that ridiculous, annoying buzzer, that kept shorting out and liked to go on randomly. Robey had an original NOS switch *without* the buzzer switch (it's like a black cup with a wire hanging out of it that fits over the entire lock assembly) but *with* the steering wheel lock. It even had an original Britax key. I figured, wow, this is a once in a lifetime chance, so I did it. I was glad I did. By the way, the electronic part of the switch is easily found and usually readily available.

Cheers!

Submitted by NE52-32043 on Tue, 10/19/2010 - 16:50

Thanks for the responses, guys. Brian, when it goes on me, it is as if I turned the switch off. Everything that is controlled by the switch goes dead, instantly. The engine will not crank. But I believe those things that are not "switched" continue to work. That's why I suspected the switch mechanism. I had this problem previously, and took the switch out, took it apart, cleaned up the insides, and the problem seemed to go away. Now, it's back.

The idea that one of the wires is bad, particularly the main feed, is somewhat appealing as an idea. I guess I need to get under there and really inspect that wire, or run a new one. This might be one for Occam's Razor.

Submitted by bblackwell@jcna.com on Mon, 10/18/2010 - 21:59

Hello Steve.
When my switch went out a few years ago, I bought the switch but just replaced the electrical rotary part of the switch and avoided the tumbler and resulting key change. there were two tiny screws that held the back half to the switch assembly, giving you everything forward of the tumblers. Then I plugged the old switch with the new back half into the harness, and it has worked ever since.

I agree with testing the switch, but each turn and familiar dash lights working or not is essentially bench testing it. When mine failed, the detents and turning torque required changed, as a result of the metal contacts finally wearing to the point of jamming and ripping many of the other contacts up with each turn of the key. When one of these switches goes in this way though, it does not come back. If your car starts again later, how are you sure it is the ignition switch? I had an original cloth wrapped negative battery cable on an XJ6 that would cause the car to just go totally, electrically dead for a few seconds, and then it would come back. It was not until I just put new cables on it as a test that the problem disappeared.

I presume everything on the car that runs with the switch on quits when it dies, like wipers, turn signals, etc. and everything else that is unswitched, like headlights keeps working, or is it everything just goes dead? If it is just the motor that quits and it restarts later, I would try changing the coil. That is cheap and easy, and most everyone has a spare laying around. If you run electronic ignition, I think those are tough on even the Lucas sport coils. Does the engine crank, but not start, or is it totally dead when it stops on you?

Submitted by DavidBarnes71@… on Mon, 10/18/2010 - 20:29

Not sure if there are any differences between the '70's and the steering column type switch on my '68 with Series II type dash... but have you looked at Lucas switch p/n 34680 ? I still have the box it came in. It has spots for 7 wire connections but do not use them all on my '68. My switch fried a few years ago and I was able to buy this one from Motor Cars LTD (I think). I was able to remove the key lock portion that came with it and put in the one for my origianl key out of the old switch.

David Barnes
'68 FHC

Submitted by dlkorock@comcast.net on Mon, 10/18/2010 - 16:11

Steve,

I would do a thorough electrical bench check on the switch before I replace it. The switches are relatively simple as you know and it would be worthwhile to attempt to repair and or simply clean the unit first, especially since they are hard to come by.
One other thing you can accomplish while on the bench is to ID the function of each terminal which will aid you in going to a series III unit if needed.

Hope this helps,

Don