O/T '92 CHevy S-10 Elec. Question

[Pherdie]

Posting here because I feel there are a few folks on here that can give me a possible answer in a short period of time. I'm asking the question for a friend who is in a very serious health way, needs the truck for his business and is trying to feed his family. Any help is appreciated.

My friend claims his S-10 will not start and he believes the problem is a missing cover from the ALDL connector (http://www.obd-codes.com/faq/read-gm...codes-free.php), which is a diagnostic port located under the steering column. Five wires run to the plug in this model truck. He said the cover has fallen off before and reinstalling the cover has made the truck operative again. Now the cover is lost.

I have a Haynes manual for the S-10, but the electrical schematics don't apparently show the ALDL port wiring. I have not been able to find any information that would support electrical circutry in the cap necessitating the cap to be in place for the truck to run. My friend is a very intelligent man but his mind is clouded from years of chemo, so I have to question his recollection. Is the cap actually required for the truck to run? If so, how can I quickly electrically emulate the cap?

Thanks for your help!

[Don Young]

I have owned and worked on quite a few vehicles with diagnostic connectors from very early ones up to OBD-II and have never seen any electrical connections in the covers. I would suggest connecting a code reader and seeing what it reveals.

[Danl]

I agree with Don on this one.....

[Willy]

In a word...no.
I used to drive one of these occasionally and have a friend with a similar unit.
Have also driven and owned several GM vehicles from the same vintage and have done OBD I diagnostic tests on several of these, and the covers on all vehicles has been just a simple dust and debris cover.
I don't believe I've ever seen an OBD port that wasn't the same.

[Toolguy]

Maybe during the cover install a loose connection was re established.

[saltmine]

I agree. Many OBD 1 & 2 equipped vehicles, including GM, don't even come from the factory with a cover in place. I've never seen any reference to a cover switch or anything else that would indicate the port cover would be required to make the truck run. I'm pretty sure that if you looked a bit closer, you might find damaged wiring or connectors that are being moved when the cover or the port is removed or installed. If memory serves, there are some starter energize wires in close proximity to the port. If one or both of the sheet metal screws had fallen out, rodent eaten wires could touch or break contact qute easily. All of them start and run with a scan tool plugged in, right?

[J Tiers]

I have never heard of the cover being important to any functioning

[danlb]

What he may have is an anti-teft device. They were popular in the early 1990s due to carjackings. A simple little socket mounted to the dash near the steering wheel shaft was wired to the ECU. Some chip was plugged in to enable the car. Pull it out and you could not start the car. I was told the car would continue running without it so the carjacker could drive away and leave you behind.

At our local dealer they wired all the cars with one. It was part of their theft control too. If you did not pay the extra $200, they simply glued the chip to the socket so you could not trigger it.

It looks enough like a diagnostic port, and the chip was embedded in a holder that might look like a cover.

Dan

[johnnyd]

This may sound way too simple...but. Try removing the main starter to battery cable from the starter. Clean it with one of those wire "toothbrushes" & re-install it.
My 1995 S-10 Blazer refuses to start about twice a year, & that's what I have to do to fix it.