94 engine harness vs 95 engine harness

A

awmcga01

Member
I'm trying to figure out if these two are the same harness? I used the search function but could not conclude a definite answer. Thanks y'all for the help I apologize it posted in the sticky thread and not the normal thread. How do I move it?
 
If they're the same, they'll have the same PN. If the PNs are different, there's something different about the harnesses. Probably the ignition system; '94 might use the older ('93) push-start ICM and '95 certainly uses the CCD ICM.

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But '94 should be CCD like '95.
 
Yes 94 & 95 harnesses are different — have different part numbers — see Finding Replacement Parts sticky
 
My '94 is CCD.

Sadly I hacked my '95 harness beyond all hope of compatibility when I converted to sequential injection, or I could test them. I still use the square engine connector, but all of the smog stuff is gone and the additional 6 injector leads have been added.
 
I know that the 12A581, main engine compartment harness has a different part number for each generation. However the 9D930, injector/sensor harness is not listed in the replacement parts list sticky and I have never had any luck finding a part number.

Anybody have the 95 pin out for the C101 connector? I have the info for the 94.
 
4 pins are different, 10, 20, 30 and 35.

94 Pin 10 = circuit 347, ground power feed from the AC Clutch Cycling Switch to the AC High Pressure Switch
94 pin 20 = circuit 883, AC pressure switch signal path for the AC Clutch Cycle Switch to the PCM
94 pin 30 = circuit 570, ground Ground connection between the Distributor and Ignition Control Module
94 pin 35 = circuit 330, power steering pressure switch - should not be applicable on a 5.8

95 pin 10 = circuit 441 power feed from the AC Clutch Cycling Switch to the AC High Pressure Switch
95 pin 20 = circuit 198 signal path for the AC Clutch Cycle Switch to the PCM
95 pin 30 = circuit 938 Not used on 5.8 Ground connection between the Distributor and Ignition Control Module
95 pin 35 = not used
 
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So I reached out to a friend with data on both year models.

Per our comparing notes, pin 10 and 20 service the same circuits in both year models but the numerical designations were changed. These should work as is.

My previous label of circuit 347 as a ground was incorrect. It is power feed from the AC Clutch Cycling Switch to the AC High Pressure Switch, the same as the 95 circuit 441. I will correct the previous post.

The 1994 circuit 883 and 1995 circuit 198 are both signal path for the AC Clutch Cycle Switch to the PCM.

The 1994 circuit 570 is a ground, but I found no interactions with this circuit with anything on the engine. I will confirm this with a multi meter on the harness. If that is true, then there should be no problem with this circuit.

Pending a little hands on investigation, I think there is no functional reason the harness will not work.
 
I'm sure the the pins function the same however they are physically different connectors (the injector harness to the main harness).

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slow94 said:
I'm sure the the pins function the same however they are physically different connectors (the injector harness to the main harness).

Sent from my Pixel 6 Pro using Tapatalk
Click to expand...

I believe you are incorrect. Can you, or anyone else provide some evidence one way or the other?
 
All the pins in C101 are the same size & gender, for all years. The "main harness" section is the dash harness section, and the injector harness section doesn't connect to it.
 
I can take pictures of a 94 and a 95 engine connector when I get gone Wednesday.

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So, I checked out the 94 Pin 30, Circuit 570 with a multi meter and found it linked up to the distributor connector, which helped me to zero in on the ignition schematics. So, that section of 570 is a ground between the distributor and ignition control module. I did not find it referenced anywhere else in the 94 EVTM as being involved with the distributor or the ignition module. Honestly, I couldn't find where is splices into to the rest of the 570 circuit...

More good news is that the 95 Pin 30 Circuit 938 is the same circuit/function. Again, I only found this in the ignition system schematic (Looking at data posted by Steve83) does not match what is indicated in the 95 C101 pin out provided earlier in the thread.

So, assuming the connectors are the same between 94/95 the two harness should be interchangeable without modification.
 
R&RFord said:
I couldn't find where is splices into to the rest of the 570 circuit.
Click to expand...
570 is used for several distinct & unconnected sections of wire throughout the truck. But they all have the same basic function, which is why they share that circuit number. So that 570 Bk/Wh between the ICM & distributor is joined to the others through the distributor body, which grounds to the block, which is grounded to the body, frame, & B- post, like all the other sections of 570.
 
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