[moon509]

On the advice of Phil I restarted this. Some of my posts will be complete reprints of the last thread. I can add wire diagrams on request Please share pertinent information and ask questions in pm's as to not clutter up the thread.

Ok guys, I have been kinda bored lately since I am low on funds to buy go fast parts. My friend Shane is installing a 5.3 in his 1999 body dropped blazer. I volunteered to repin the harness. This thread will be a tutorial on repinning a 2002 Silverado harness to work in a 1999 Blazer or s10 with 4.3. I will do my best to document and post the whole build along with a spread sheet for repin and such. I will also need help along the way.

His blazer build thread : http://www.s10forum.com/forum/f98/sfbd-99-blazer-help-461568/

His underhood fuse box and ecu will be mounted inside under the dash. I will remove the rear O2's, cruise control, ABS, Windshield sprayers, and any other wires related to these and not needed. The C4 to the old ECU has a lot of unused wires that will get removed.


Here is what I am starting with.




Got to mess around with it tonight, the benefit of working nights and not having shit to do at midnight. I started by stripping all of the all loom off along with most of the tape. Once its all label I will remove every bit of tape.





pretty much bare



So I got a little work done tonight. I started with the red and connectors and unpinned all the wires that are not going to be used. The red and blue pin covers come off pretty easy, just depress the white part at each end of the cover. Once the covers are removed, push the pin up that you want to remove. Lift the white tab and pull the wire and pin out the back of the connector.

There were a few black wires from the rear o2's that went to a large ground splice pack. I clipped the wires as close to the splice pack as I could and will come back to them later to tape up, also from the tan wires from the o2's.

Once I removed the ecu pins I traced them back to there connectors and removed them all or just the pin depending on the connector.

ground slice pack, bad pic



everthing removed so far, rear o2 connectors, some evap and a/c connectors.



lol, so I may have jump started this today. My friend came over. The harness is going in to his blazer. The ecm and underhood fuse buse will be mounted under the dash on the passanger side. The harness itself will be stripped down to the bare essentials to run the motor, no a/c, cruise control. After looking at the un-loomed harness we decided to unpin the entire harness. Using my motor as a template we ran all the wires to the existing plugs and taped it together. We left all the length to cut and solder them to there new homes.

I will try to be more detailed with the c2 and fuse buse wiring, I feel like a ruined a perfectly good how to thread,

Here is a few pics of the taped harness.





Working on the harness and my friends house.







Finishing it up at my house






I just finished up the harness. The C2 underhood fuse buse is complete and I think I will need two more wires to the ecu and that's done. I did mark all the wires that go to the c101 and c4 blk connector from the old ecu. I took pretty detailed notes. As soon as I am done transferring the notes to more legible pin-outs I will scan and post them.



picture of said blazer and test fitting the harness.

 

[moon509]

Below are my notes from making a harness. This harness is basic and I have not completely figured out the fuel system yet. My friends blazer has a fuel cell with a 90ohm one wire sender. I need to find out how to wires this and if it will work with the s10 gauge cluster.

This harness has no provisions for:
EGR
EVAP
POST CAT O2'S
HVAC- NO BLOWER, HEAT OR A/C (WILL RUN AN AFTER MARKET HEATER DEFROST UNIT)
CRUISE CONTROL
WINDSHIELD SPRAYERS
ABS

Having listed the above, the harness is stripped out and basic as needed.

We first have the C1 BLUE and C2 RED all circled number are used. If there is not designated connector the wire goes to the listed part. C2 refers to the underhood fuse buse C2. The park neutral position switch also has a C1 & C2 and I list it as PNP C1 or C2. C175 refers to the round trans connector. C101 is from the s10 harness near the old ecu. C4 is the black connector from the old s10 ecu.

Grounds listed:
Ecu C1 1,40 / C2 1,40
MAF
PNP Switch C2-D
I grounded them together on the cylinder head

Ignition coils (2 BLK wires, one for each bank)
O2 sensors
C2-E7, F-6 & A6
Grounded to the other cylinder head

I have to give credit to http://lt1swap.com/wiringharness.htm for the C1 & C2 layout. I liked there format with the blue, yellow and red information. It looks a lot better then a plain C1, C2 pinout with writing on it.

 

[moon509]

C2 from the underhood fuse buse





C175 transmission connector



Park/ Neutral position switch C1 & C2





C4 BLK connector from old s10 ecu





C101

 

[moon509]

I will be working on the fuel pump and sender system next. His sender is a 40-90ohm. He's going to order the proper 240-33.5 Ohm sending unit.

 

[Tuckin15's]

Subd

 

[moon509]

brads99xtreme point out to me that C4-E goes to C2-50, but it should be C4-3. I will have a mode change out the picture with the correct one.

Again, if you see any changes that need to be made, let me know.

 

[philntx]

We'll keep this open for now. If you are going to post to it, please make sure your comments are related to the thread.

Phil

 

[moon509]

I want to keep this going if we have harness info to add pm me if it needs to be formatted.

 

[Chevygreg71]

Is their a reason the pictures will not load for me?

 

[moon509]

Is their a reason the pictures will not load for me?

They are loading ok for me. I can email the pinouts if you need.

 

[greencactus3]

can you also post c104 pinouts for the 4.3?
and also whatever the connector going to the 4wd stuff is called too
Thanks!

 

[Chevygreg71]

I need fuel pump pin out. Yes send ne what u have [email protected]. im using 99 4.3 blazer fuse box with a 99 sierra 5.3 engine harness. Its 4x4 thank u moon509 im glad to see you did this for people like me..

 

[Chevygreg71]

Do any of the ground wires that are in spicr pack go to fuse box? Or can u just ground to engine?

 

[moon509]

can you also post c104 pinouts for the 4.3?
and also whatever the connector going to the 4wd stuff is called too
Thanks!

I am pretty sure C104 is fullsize specific. The 99 4.3 does not have one. If you want me to identify a connector, you need to post a pic or be more specific. This "the connector going to the 4wd stuff" tells me nothing. Description of where its at and a pic would be helpful.

 

[moon509]

Do any of the ground wires that are in spicr pack go to fuse box? Or can u just ground to engine?

I need you to be more specific, which splice pack? Where is it?

 

[greencactus3]

I am pretty sure C104 is fullsize specific. The 99 4.3 does not have one. If you want me to identify a connector, you need to post a pic or be more specific. This "the connector going to the 4wd stuff" tells me nothing. Description of where its at and a pic would be helpful.

I believe c152 is the fullsize equivalent of c104

I see the title block here at the bottom,

I'm not sure where the 4wd stuff connector is actually, I currently know it contains circuit #s 1694 and 1695.
It is the equivalent connector for the s10 4.3 as the fullsize's c153

 

[moon509]

I believe c152 is the fullsize equivalent of c104

I'm not sure where the 4wd stuff connector is actually, I currently know it contains circuit #s 1694 and 1695.
It is the equivalent connector for the s10 4.3 as the fullsize's c153

I will check on this and post, I am almost positive the 2.2 and 4.3 c104 will be pinned the same. Sorry for the late reply.

 

[moon509]

includes c104 2.2 and 4.3

 

[greencactus3]

thanks!

 

[99SSCHEVY]

Wow moon that is a lot of work on that harness. I think I'll stick with the high voltage wiring that I do. Just reading in on all the info on my swap. 2005 ho 5.3 into my 2002 xblaze.