Unidentified Flying Plug

[85rollback]

Hi All, Thinning out old rats nest wiring is super satisfying. But I have encountered this abandoned plug under my cab and chassis '85 6.9. I have had no luck tracing back the colors. Does anyone recognize this plug?

 

[Rdnck84_03]

If you're truck is a manual transmission it looks like the backup light switch plug.

James

 

[Nero]

I second that, looks like a reverse plug connector

 

[XOLATEM]

I vote to get a test light...or better yet...a Power Probe...and find out what it does....with the key on and off...

Amazon.com

I second and third the previous diagnosis's...you guys are sharp...

I had a power probe for years...and never used it...and then...once I started using it...I just could not stop...coolest electrical device ever...

 

[XOLATEM]

Thinning out old rats nest wiring is super satisfying.

Yeah, tell me about it...I went through the same thing with my '85 CC..

I could not believe how screwed up the tail light and trailer connector harness was on mine when I got it....and I did not have a wiring diagram...but I fingered it out...

I should have saved the old stuff and taken a picture of it...

One of the few things in my life that I did not see any other use for it other than vigorously and with much flair flinging it into the nearest trash can...I should have done some kind of ballet move with it...

I started with a pair of snips...under the truck and laying on a few sheets of cardboard...black soot everywhere...and bared the harness back to the point of it not being molested...and hesitated a second....no going back after the next act...and snipped that crap off and away...

You ever hear of a shark feeding frenzy...? I started snipping everywhere...all of that twenty and thirty year-old-stuff was going away from here...!!!

I took the best bit of a harness diagram I could find on the internet...the instuctions for a trailer wiring harness... the instructions for a modern RV connector plug and receptacle...with a 4-flat option...and the instructions for a trailer brake unit that I had on hand...and made up an extensive color-code-to-function chart and diagram...

....sorted out every bit of my wiring supplies and tools...organized it into bins and bags...made a few trips to the parts store and bought some stuff from Work...gathered up any marerials I might need...

...and attacked that job with the ferocity of a Guy that wants NO MORE TROUBLE with any wiring problem while out on the road and towing a heavy load....

It all turned out pretty good...crossed the 'T's' and dotted the 'I's'...

THAT was satisfying...

I hope it is as good for you as it was for me....

I can thank the job I had at a paving company for getting me militant about wiring...

 

[Jesus Freak]

Definitely reverse lights plug. If it isn't the other 3 guys will eat their hats.

 

[Old Goat]

I vote to get a test light...or better yet...a Power Probe...and find out what it does....with the key on and off...

Amazon.com

I second and third the previous diagnosis's...you guys are sharp...

I had a power probe for years...and never used it...and then...once I started using it...I just could not stop...coolest electrical device ever...

Now you made me go search....

Here is this one on Amazon for $109

https://www.amazon.com/Power-Probe-III-Clamshell-Automotive/dp/B00G4YUWMC/ref=asc_df_B00G4YUWMC/?tag=hyprod-20&linkCode=df0&hvadid=309806250188&hvpos=&hvnetw=g&hvrand=4218974007824254195&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=1022653&hvtargid=pla-376660908451&psc=1&mcid=3add0ff52e2131bca12038d92d00de75&gclid=Cj0KCQiAm4WsBhCiARIsAEJIEzU3PjSyqvqxpZmC1UuKyKwGkwADbv07wJlYm5e9AwRjTULholEqpC8aAtlgEALw_wcB

Then for a few dollars more get the case and a few accessories. $114

https://www.amazon.com/Power-Probe-III-Case-Acc/dp/B005MVB3S0/ref=asc_df_B005MVB3S0/?tag=hyprod-20&linkCode=df0&hvadid=312065537890&hvpos=&hvnetw=g&hvrand=4735327469153045605&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=1022653&hvtargid=pla-492036024479&psc=1&mcid=ef0222fbeeb2351b9ab0618a5bde1139&gclid=Cj0KCQiAm4WsBhCiARIsAEJIEzWcCfl13gA2EemMlC0PN6zMbtlnOmaz0rrYCKp63PHGTKqMfWuDrUAaApVgEALw_wcB

Harbor Freight has the same one for a much higher price. $179

PP319FTC Circuit Tester

Amazing deals on this Pp319Ftc Circuit Tester at Harbor Freight. Quality tools & low prices.

www.harborfreight.com

Goat

 

[typ4]

Yeah, tell me about it...I went through the same thing with my '85 CC..

I could not believe how screwed up the tail light and trailer connector harness was on mine when I got it....and I did not have a wiring diagram...but I fingered it out...

I should have saved the old stuff and taken a picture of it...

One of the few things in my life that I did not see any other use for it other than vigorously and with much flair flinging it into the nearest trash can...I should have done some kind of ballet move with it...

I started with a pair of snips...under the truck and laying on a few sheets of cardboard...black soot everywhere...and bared the harness back to the point of it not being molested...and hesitated a second....no going back after the next act...and snipped that crap off and away...

You ever hear of a shark feeding frenzy...? I started snipping everywhere...all of that twenty and thirty year-old-stuff was going away from here...!!!

I took the best bit of a harness diagram I could find on the internet...the instuctions for a trailer wiring harness... the instructions for a modern RV connector plug and receptacle...with a 4-flat option...and the instructions for a trailer brake unit that I had on hand...and made up an extensive color-code-to-function chart and diagram...

....sorted out every bit of my wiring supplies and tools...organized it into bins and bags...made a few trips to the parts store and bought some stuff from Work...gathered up any marerials I might need...

...and attacked that job with the ferocity of a Guy that wants NO MORE TROUBLE with any wiring problem while out on the road and towing a heavy load....

It all turned out pretty good...crossed the 'T's' and dotted the 'I's'...

THAT was satisfying...

I hope it is as good for you as it was for me....

I can thank the job I had at a paving company for getting me militant about wiring...

I advise people to do exactly this when they've just acquired a truck that has a bunch of hacked up wiring and add-ons. Put it back to stock and almost all of your problems will go away. Then you can properly add accessories.

 

[Jesus Freak]

I advise people to do exactly this when they've just acquired a truck that has a bunch of hacked up wiring and add-ons. Put it back to stock and almost all of your problems will go away. Then you can properly add accessories.

My 86 bronco was like the Texas chainsaw massacre under the dash and hood. I've almost got it to rights