wiring diagram cx100

[ital4me]

Greetings,
    Does anyone know of a wiring diagram for a 1979 cx100? I have one from thisoldtractor and one that I had kicking around. I believe one for a sp1000 and the other I am not sure. They look almost identical except is for the printed circuit board in the dash with the warning lights. They have the same two major connectors although the numbering scheme is different. Here is the odd part. Some of both of them is right and obviously the same wrong. I am wiring an aftermarket  light and horn switch. Here is the embarrassing part. I installed this maybe 10 years ago and disconnected it as part of the recommissioning. I thought I had the right schematic. Wrong! It was working great before I disassembled it. I now have it all working with the exception of the headlight warning lights. My online search has turned up nothing.

[ital4me]

I did find two at guzzitek. One is Carl Allison's for a 1978 1000 SP that looks promising and another for the same bike that is different, much harder to read. Nothing specific for the CX100. I'll let you know what I find out.

[blackcat]

I would think that the LeMans II harness would pretty much be the same harness as the CX.

https://www.thisoldtractor.com/guzzi007/pdfs/1978_LeMans_II.pdf

[ital4me]

Hey thanks Blackcat, That is nice and clear and a great format. One exception, the 12 pin connector, #7 has no numbers on it. They aren't in numerical order and it appears not the same from model to model. With a some searching I found that same print with the numbering. Hopefully it will work. I'll let you know. I found several different formats for these diagrams. This is the easiest to read.

[ital4me]

Just and FYI, I have been on this site for many years. I lost some stuff on the computer and do to an illness wasn't that active for a couple of years. Luap helped me get my name back. Pete Roper was active then and was a great resource. I hope all is well with him. So for what it's worth, I am not a "new egg" and I am a 2024 contributor despite not having the tag.

[blackcat]

Hey thanks Blackcat, That is nice and clear and a great format. One exception, the 12 pin connector, #7 has no numbers on it. They aren't in numerical order and it appears not the same from model to model. With a some searching I found that same print with the numbering. Hopefully it will work. I'll let you know. I found several different formats for these diagrams. This is the easiest to read.

This is from This Old Tractor for the 12 pin connector:

“Plug information:

Position 1: red/black (power in for headlights)
Position 2: empty
Position 3: black (ground in for horn and flash relay)
Position 4: red (power in for parking lights - almost never needed with non-original switches)
Position 5: green (power out to headlight low beam)
Position 6: brown (power out to headlight high beam)
Position 7: yellow (power out to parking lights)
Position 8: green/black (power out to left turn signals)
Position 9: pink (power out to right turn signals)
Position 10: gray (ground for headlight high beam flash relay - almost never needed with non-original switches)
Position 11: white/black (ground to horn)
Position 12: orange (power in for turn signals)”

https://www.thisoldtractor.com/for_sale_wiring_harness_tonti_le_mans_cx_100.html

[ital4me]

Wow, thanks again! That is awesome. What I need and no schematic to deal with. You are the man.

[blackcat]

Wow, thanks again! That is awesome. What I need and no schematic to deal with. You are the man.

Thanks but Greg is the guy. I'm terrible at electrics though better than when I first owned purchased the CX.

"I am wiring an aftermarket  light and horn switch."

Which brand switch are you using because Greg sells a short harness for Domino (what I have on my CX) and some other switches. I'd scroll through that link and see if it works for whatever switch you are using.

[ital4me]

With your link I found this adapter that end all problems I hope.

"Hi Gregory,
    A gentleman from Wild Guzzi just sent me your link for your pin out diagram for the left hand switch on my 1979 CX100. Awesome enough but then I see your adapter for the K&S handle bar switch set. Just what the doctor ordered! I can't find any documentation from when I bought the switch years ago but it looks exactly like the K&S in your article, connector and all. I would like to order one please.
Thanks, John"

Again, thank you Mr.Cat!

[Shiny Hat]

This won’t help the OP but on the print relays 32 and 37 shown, 32 is wired correctly based on the terminal number standard, 37 is not. If you were to fault trace them based off the PIN numbers relay 37 would cause you issue’s.
I love to look at prints and can do it all day. Just mentioning it as useful or unusual information, your choice.

[blackcat]

Greg makes great wiring harnesses for Guzzi's. I used his wiring harness for my LeMans I,  I used the original switches but Greg suggested using his bank of relays as I didn't want any meltdowns. I don't have those relays on my CX but it is something that I will install in the future.

[Shiny Hat]

I guessing Greg is the man behind this old tractor. That site is worth its weight in gold. I was able to find the hydro recall work instructions plus the lifter spec. It made my life a whole lot easier.

[ital4me]

 I received the wiring adapter from Greg at ThisOldTractor. Plug and play. Very nice quality. I wish I had known about this adapter, would have saved lots of aggravation. Thanks for the tip!

[blackcat]

Yes, Greg makes top notch wiring harnesses. I have a NOS harness for my 1000S which I purchased a dozen plus years ago and I don't think it is as good as Greg's work.