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Bulkhead connector pinout?

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608 views 14 replies 4 participants last post by  AstroWill  
#1 ·
Hello all,

Wondering if somebody has the pin out for the bulkhead connector I believe is labeled as c100. It's the connector that passes through the firewall just behind the battery. I need the pin out for the engine side for a '96 and an '87. I just put the 96 motor in my '87. Any help is much appreciated. Thanks guys.

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#2 ·
Poking around the charm.li site might be helpful.I found this for the 87 (I didn't look for the 96, but it should be there too):

Autozone has diagrams for the 87:

And the 96:

I don't know if these links will work for you, they won't open for me in a different browser. I went to their website and clicked on Menu- repair help- repair guides- and entered the info for both vans, I found the pinouts under chassis electrical. this is where I got the wiring info for my V8 swap too.

I think the easiest route is to replicate the way things were with the original engine, it's what the computer is looking for. That's what I did for my swap- I recreated what the computer was expecting to see.
 
#3 ·
Good call on the charm website. I was able to find the 96 pinout. I looked through 85-90 for the pinout, unable to find that still. I'll keep searching. But thanks again, that was a ton of help.

I do have a lot of diagrams for the '87, but they don't give the pin out number. So I would literally have to trace each wire through the entire harness. I'll keep searching. Thanks for the help again.
 
#4 ·
There is a complete pack of wiring diagrams for our vans available on the interwebs, it covers ALL years from 1985 to 2005.

 
#5 ·
Thank you AstroWill... I did have a chance to look through it, although I wasn't able to find what I was looking for. Maybe I just overlooked something, but I didn't see something with a pin out for the main engine harness on the 87 Astro. I'll put some more time into it and look harder. Thanks again.. 😊
 
#7 ·
C100 I/P junction block. I have it for the 89, but couldn't guarantee that it's the same for your 87. It's in the Electrical Diagnosis and Wiring Diagrams book.
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#9 · (Edited)
87CL and Astrowill.. I have that also in the 1990 service manual..except..what you show only covers 1 item on 1 page of the electrical diagrams. There are a lot of other wires that go in there for different items that might cover 15-20 diagram pages..

I was looking through the service manual but couldn't find ALL the wiring found on one page for that C100 connector.

My speedometer suddenly isn't working along with the odometer.. and I'm having to track across about 10-15 different pages and the C100 was shown in several of those depending on what function or part you were tracking. I think you will need the book,at least the '87 Electrical Diagrams, to chase that set of pins/wire numbers..and maybe the other also to see how they compare for pins/functions/connections,etc... Then figure out which wires/pins might be in the same spots and which ones you need of the total mass for your newer engine into the older van.

The Electrical diagram books are configured of pages specifically for each function..and divided into chapters.The page after the diagrams show what connectors are shown on that diagram(listing says C100..).Then you have to find that connector to see where the wires go..and if you need them for your engine/van/application.. for instance Fuel Pump/Idle air Control ( diagram page36)..Speedometer/Odometer (90.without RPO52..other following pages with),Gages and Indicaters (page 100) Again..the following pages list the C100 as a component/connector for that page..(37),91,101.,etc. There are several other C100s in listings on other pages..(but components not called out as "C100..that could be that..)

I'm not sure of what changes are made for the pinout cover/wiring layouts..what pins cover what that might be the same or different..or if some maybe some other circuits..within that cluster for both years..and what could be the same between those two years.

I'm chasing wires through the C100 for the VSS in the transmission to the DRAC hooked to the ECMsc..,I/P,etc . Mine might have 20 pins/wires through that C100 connector. Would it help you to see it?.. probably not because mine is AWD,4WAL,etc.. and 4.3 TBI Z(is yours that?). :eek:

EDIT..AStrowill..You've looked through more of the service/electrical books than I have,since I only have the 1990....Do you find the circuit nymbers remain the same for the different year van..as far as what they do or how they are related to a certain function or part within the circuits?..Can I assume the black wire is always ground for all the years and the number 150 used for that..or X/Y color wire will be for the same sensor,door lock,etc..

I'm wondering if the pinout covers are the same across the vans as far as the number of pins and where they are...in the same spots.but only certain ones are used for the same functions/wire numbers,etc..so one van needing 8 numbered circuits verses one needing 12..follow the same layout with the one needing 8 having 4 empty pins?.The 8 for both that are used will remain in the some place? I guess that's what I'm asking...
 
#10 ·
realityguy said:
87CL and Astrowill.. I have that also in the 1990 service manual..except..what you show only covers 1 item on 1 page of the electrical diagrams. There are a lot of other wires that go in there for different items that might cover 15-20 diagram pages..
Yes, I sent him the whole thing.

realityguy said:
EDIT..AStrowill..You've looked through more of the service/electrical books than I have,since I only have the 1990....Do you find the circuit nymbers remain the same for the different year van..as far as what they do or how they are related to a certain function or part within the circuits?..Can I assume the black wire is always ground for all the years and the number 150 used for that..or X/Y color wire will be for the same sensor,door lock,etc..
I look at so many different ones that I never assume any circuit number or wiring color is going to be the same. Sure you can find many that are the same, but that 1 time you assume and it will be wrong.
 
#11 ·
Okay..thanks for getting back..I looked at the book again and found: Page 16 Power distribution,ignition,26,ECM inputs 28,ECM outputs 30m,Fuel pump/injector control 32,Torque converter/clutch 34,and Backup lights 67..
Kind of why I asked the questions..

I know they kind of used whatever color wire seemed "close" to what was written in the diagrams,and what they had in stock at the moment..sometimes not nearly the same colors.. I had my cap off for that C100 a few days ago (if it relates,pin comparison?)..I had taken a picture at the time..partially through the mess I still need to finish cleaning out... Perhaps he can figure out what pin is where/wires/numbers(I can see of it matches your chart/number locations. ..and see how they relate.I didn't have a toothbrush handy at the time and it is full of a black tarry mass.I pulled out some of it,maybe enough to reference where the pins are located on the 1990 Cl AWD/4WAL
..easier to see the pin locations on the socket side.
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#12 ·
Thanks for everyone's help. The 87 is currently running smooth with the 96 drivetrain. Everything seems to be functioning as it should. If anyone else wants to put a 96up motor in their 95 down, hit me up. It's really not that hard to do. Just figuring out the wiring was the worst part. But with the help I got here, I got it done. And in the future I'd be able to help somebody else.👍🏽👍🏽👍🏽
 
#15 ·
If anyone else wants to put a 96up motor in their 95 down, hit me up. It's really not that hard to do. Just figuring out the wiring was the worst part. But with the help I got here, I got it done. And in the future I'd be able to help somebody else.
For sure post what you can, I know I will be in the same boat one of these days, putting a late 90s AWD drivetrain into one of my late 80s Tigers.