OBS UVCH to newer style wiring harness conversion

maplemale · Mar 19, 2015

Anyone done this before? Know of a good write-up? Thought it would be easy enough, but at first glance it looks like there's 10 wires on the OBS (1 115v dc common per plug) and on the newer style pigtail, it's got 9 wires. I might be able to figure this out with two diagrams. I find plenty for the old style plugs and am referencing this:

http://www.thedieselstop.com/faq/9497faq/tsb/tsb/sia/siamain.htm

But, can't find a diagram for the pinouts on the newer style.

zilla68 · Mar 19, 2015

yes it has been done, either here or on psn, there is a write up also I believe

Swaan · Mar 19, 2015

It's not hard. I did this on my 97. I didn't have no wiring diagram. But it's not hard. Just take your time do a proper job. You got to cut all the wires and splice in the new Sd pigtails.
Then just get SD uvch for both sides and your good.
It's a good upgrade over the stock obs harness. The pins are bigger and so are the wires.

Peroni · Mar 19, 2015

Swaan said:
It's not hard. I did this on my 97. I didn't have no wiring diagram. But it's not hard. Just take your time do a proper job. You got to cut all the wires and splice in the new Sd pigtails.
Then just get SD uvch for both sides and your good.
It's a good upgrade over the stock obs harness. The pins are bigger and so are the wires.

I did the exact same thing to my 97. Just work carefully and double check everything. It really wasn't a difficult job at all.

Krause · Mar 20, 2015

maplemale said:
Anyone done this before? Know of a good write-up? Thought it would be easy enough, but at first glance it looks like there's 10 wires on the OBS (1 115v dc common per plug) and on the newer style pigtail, it's got 9 wires. I might be able to figure this out with two diagrams. I find plenty for the old style plugs and am referencing this:

http://www.thedieselstop.com/faq/9497faq/tsb/tsb/sia/siamain.htm

But, can't find a diagram for the pinouts on the newer style.

I believe the extra wire is because the OBS utilizes two ground wires, and the SD only uses one. From what Ive read, you just combine the OBS ground wires into one and connect to the single SD one, and the rest is just connected together. Havnt done myself, but have researched as its one of the next things to do.

-Andrew

Arisley · Mar 20, 2015

You will also need new gaskets.

97stoker350 · Mar 26, 2015

Got a set of gaskets if your interested

maplemale · Mar 30, 2015

97stoker350 said:
Got a set of gaskets if your interested

Thanks! Appreciate that!

I already got the gaskets actually. When they came with the single plug and the new pig-tails, that was what prompted my questions about the conversion. I guess I was just being lazy looking for an idiot proof writeup. Will figure this out...

PS: I wonder how long one of the glow plug wires had been roasted off completely?