LS1 harness: Start to finish
#54
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Re: LS1 harness: Start to finish
Using these pinouts, label each wire for every connector. I like to wrap the wires every 6-8" to cut down on tangles. Label the PCM connector and pin assignment as well as the connector name incase you mix the pin up. There are up to 160 pins and thats alot to get mixed up
The pinouts were recycled from my 0411 swap so ignore the Express van side. Also, Blue is C1 and Red C2. This gets confusing so my pin assignments are labeled by color rather than C1/C2 Ex: R9 = Red pin 9, B42 = Blue pin 42. Some colors changed over the years. For a specific year/model breakdown resort to LS1tech or chevythunder
Drape the wire groups over the engine and plug 'em up. You should get a general feel for the shape of the end harness
Once the routing is decided, bind the groups together with electrical tape. Ensure no connector is pulled taught and has plenty of length
The pinouts were recycled from my 0411 swap so ignore the Express van side. Also, Blue is C1 and Red C2. This gets confusing so my pin assignments are labeled by color rather than C1/C2 Ex: R9 = Red pin 9, B42 = Blue pin 42. Some colors changed over the years. For a specific year/model breakdown resort to LS1tech or chevythunder
Drape the wire groups over the engine and plug 'em up. You should get a general feel for the shape of the end harness
Once the routing is decided, bind the groups together with electrical tape. Ensure no connector is pulled taught and has plenty of length
#55
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Re: LS1 harness: Start to finish
Any 24x LSx using a 4896 or 0411 PCM (most common two). Also fits 58x LSx with the leignfelter conversion box
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Re: LS1 harness: Start to finish
Those are the compatible PCM serial numbers for that pinout. 24x/58x is the crank reluctor type. The older PCM cannot understand the newer reluctor so the converter box changes a 58x signal back to 24x so the older PCM can be used to control the newer engine
LS1/6/99-06 truck engines are all 24x
LS3/4/7/9/07-present trucks are 58x
LS2s can be either way, check before hand
Yes, cut the ground commons and solder them back together at the end
LS1/6/99-06 truck engines are all 24x
LS3/4/7/9/07-present trucks are 58x
LS2s can be either way, check before hand
Yes, cut the ground commons and solder them back together at the end
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Re: LS1 harness: Start to finish
on the pinup provided, it says #8 put tps reference and it says the wire is grey, all of my wires aregreen or blue, which one goes where???
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Re: LS1 harness: Start to finish
What kind of wierd harness are you working with?
A GRY TPS 5v ref
B BLK (or PPL) low ref
C DK BLU signal
A GRY TPS 5v ref
B BLK (or PPL) low ref
C DK BLU signal
#61
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Re: LS1 harness: Start to finish
never mind i had the wrong sensor, i have very limited info on these types of motors, but on the blue pin place, #8 doesn't have a place for the pin to go, so i looked up a pin up particularly for 4.8's and got that fixed
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Re: LS1 harness: Start to finish
do you have to put the 02 sensors in? is there any way you can have a pcm tuned to do away with those?
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Re: LS1 harness: Start to finish
pocket i've got a real bad feeling about this wiring, also i have a few more questions...
1. does the alternator hook into the PCM or the car harness?
2. is there another name for the MAF, because i can't find mine anywhere
3. the crank sensor i have is cut, what do i do to fix that
4. PLEASE HELP ASAP!!!!
1. does the alternator hook into the PCM or the car harness?
2. is there another name for the MAF, because i can't find mine anywhere
3. the crank sensor i have is cut, what do i do to fix that
4. PLEASE HELP ASAP!!!!
#65
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Re: LS1 harness: Start to finish
1) PCM
2) MAF, Mass air etc
3) Use a 3 wire MAF connector from any 90's GM car
4) You lucked out because i sat down for a break just now
2) MAF, Mass air etc
3) Use a 3 wire MAF connector from any 90's GM car
4) You lucked out because i sat down for a break just now
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Re: LS1 harness: Start to finish
do you know the specific pins that the ALT goes 2? if not i can sit down and look through anll of the pins i have and see, did i make a bad choice by using a 4.8 PCM pin up?
#71
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Re: LS1 harness: Start to finish
PCM/Fuel battery 12v come from the 20A fuse near the battery
HO2s are on the PNK/BLK emissions fuse from the C100
HO2s are on the PNK/BLK emissions fuse from the C100
#72
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Re: LS1 harness: Start to finish
Damn dude! Thank you for this thread. I have saved this for when the time comes to do my swap. I appreciate it!
#74
Re: LS1 harness: Start to finish
this is my 1st post here (found link on NastyZ28), and i have read lots of wiring posts. this one is the easiest to follow and very thorough. should be a Sticky.
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Re: LS1 harness: Start to finish
You can use any color instead of red, just shave the little tabs off with a razor
this is my 1st post here (found link on NastyZ28), and i have read lots of wiring posts. this one is the easiest to follow and very thorough. should be a Sticky.
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Car: 1991 Chevy Camaro Z28
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Re: LS1 harness: Start to finish
this is by far the biggest headache of my life. completely depinned harness, not a single pin or connector labeled.
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Re: LS1 harness: Start to finish
i used my fingernails. if you push the pin in slightly before lifting the retaining tab it might help.
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Re: LS1 harness: Start to finish
Has anyone installed the E38 pcm and harness into a 3rd gen?
Last edited by Heritage Z; 10-21-2012 at 01:58 PM. Reason: Dumb question
#83
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Re: LS1 harness: Start to finish
i have a question about your pinouts. is that set up for a manual trans car or auto?
#84
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Re: LS1 harness: Start to finish
Both
You ignore the parts that do not apply to your build IE, If running an auto, the reverse lock, CAGS are both irrelevant
You ignore the parts that do not apply to your build IE, If running an auto, the reverse lock, CAGS are both irrelevant
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Re: LS1 harness: Start to finish
im so lost on the whole ls harness I got my 91 harness done but idk were to start on my 5.3 harness im so lost idk what half the connectors are and the whole c100 c101 c105 220, 230 im completely lost on I got all the pin outs for my pcm but idk were to start and were to connect to third gen harness and im switching to a ls2 intake from a dbw truck intake and idk were I need to pin for the tps iac etc im just so lost any kind of help or more indepth would help ik I gotta change injector plugs since im changing intake I have a 04 5.3 harness and pcm im new to all this stuff and I think I did third gen harness right but idk and the truck harness has the fuse block idk what to do with that just any kind of help will be good
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Re: LS1 harness: Start to finish
You may want to start by researching the 04 PCM, in regards to it being a drive by wire PCM. As far as I know, the 04 PCM cannot be converted to a drive by cable configuration. A 99-02 PCM would be ideal, but if you have the electronic gas pedal and TAC module, the drive by wire can be retained.
Pocket has a thread here somewhere with pictures, to help identify plugs, so you can easily decide what you need and what goes.
Pocket has a thread here somewhere with pictures, to help identify plugs, so you can easily decide what you need and what goes.
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Re: LS1 harness: Start to finish
The 04 gto is drive by cable and it uses the same PCM I'm gonna print the pin outs for it tomorrow I just got off the phone and they explained it to me I think I got it at the moment and iv done a lot of reading on all this I have the parbt number and connectors the harness Prep and this fourm lots of times
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Re: LS1 harness: Start to finish
I have a 04 blue green PCM but I'm gonna check all data today at school
#90
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Re: LS1 harness: Start to finish
Alldata wont have the answer on the PCM. You have to open it up and look for yourself
If the PCM came from a DBC engine, it will work. If it came from a DBW engine, you have to inspect
http://www.lt1swap.com/cable_conversion.htm
If the PCM came from a DBC engine, it will work. If it came from a DBW engine, you have to inspect
http://www.lt1swap.com/cable_conversion.htm
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#91
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Re: LS1 harness: Start to finish
Where do the pink and black wires from the Bank 2 Sensor 1 oxygen sensor go to? Can't find them in pinouts
Edit: ok, I get that they don't go to the pcm because they don't have pins. Where do I route them?
Edit: ok, I get that they don't go to the pcm because they don't have pins. Where do I route them?
#93
Re: LS1 harness: Start to finish
I have completed the DIY harness 99 LS1/4L60E combo into an 87 S10 Blazer. All of the wiring schematics were bounced off of this post, the famous "DIY LS1 swap into anything" book, Blazer wiring diagram and the 99 Camaro wiring diagram. I have everything installed and sitting in nice and pretty, but when i took it on its maiden trip felt some issues.
On acceleration.. shifts from 1st to 2nd harsh enough to chirp tires, 2nd to 3rd normal, 3rd to 4th normal. However.... cruising down the highway about 65-70mph it only stays in 4th for about 15 seconds, acts like it shifts into neutral for about 5 seconds then downshifts.
I have hooked up an LED light to R42 "TCC enable circuit" to see if the converter was locking up when its supposed to(haven't driven it since). I also noticed i did not have anything hooked up to B33 "TCC Brake Switch". Would not having a 12v power source hooked up to B33 affect the shifting of the transmission? and do you have any ideas on a fix?
On acceleration.. shifts from 1st to 2nd harsh enough to chirp tires, 2nd to 3rd normal, 3rd to 4th normal. However.... cruising down the highway about 65-70mph it only stays in 4th for about 15 seconds, acts like it shifts into neutral for about 5 seconds then downshifts.
I have hooked up an LED light to R42 "TCC enable circuit" to see if the converter was locking up when its supposed to(haven't driven it since). I also noticed i did not have anything hooked up to B33 "TCC Brake Switch". Would not having a 12v power source hooked up to B33 affect the shifting of the transmission? and do you have any ideas on a fix?
#94
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Re: LS1 harness: Start to finish
If theres no codes, chances are the wiring is fine. Can always double check it though by ohming out the circuits between the PCM and trans. Open circuit means issue, but it will almost always throw a code of some sort
Ive never not wired the brake switch in, so I cant tell you the symptoms related to it, but I can say it is required. Your 87 will have a compatible switch on the pedals, so wire it in and see if it helps
Ive never not wired the brake switch in, so I cant tell you the symptoms related to it, but I can say it is required. Your 87 will have a compatible switch on the pedals, so wire it in and see if it helps
#95
Re: LS1 harness: Start to finish
Thanks Pocket!!
Ill hook everything up today and see what is going on, may not get to drive it though... we got about 6 inches of snow last night and don't think that would be a good combo..lol! I am hoping that it is something simple like that.
I did the completed swap and wiring in a month and a half last Mid- October/November and have been working out gremlins since.... kinda one of those frustrating, ongoing deals.
Ill hook everything up today and see what is going on, may not get to drive it though... we got about 6 inches of snow last night and don't think that would be a good combo..lol! I am hoping that it is something simple like that.
I did the completed swap and wiring in a month and a half last Mid- October/November and have been working out gremlins since.... kinda one of those frustrating, ongoing deals.
#96
Re: LS1 harness: Start to finish
I have a question im doung my wiring and i cut off the fuse block now my question is i know the pink needs to go to the ignition switch and orange to the battery but what do i do with the rest of the wires that were on the fuse block? I need help asap
#97
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Car: 91 z28 convertible
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Re: LS1 harness: Start to finish
im guessing this is very similar to lt1 harness but just a question my harness has four connectors into the computer how would I go abouts getting that done ive got a 97lt1 t56 out of a z28 going into 91 z28
#99
Re: LS1 harness: Start to finish
Wow, this thread is incredibly helpful... I wish I'd found it before I got neck deep in building mine from scratch Just another one of those things where I do a bunch of research and think I have it all under control, then get part way into it and realize I have no idea and end up spending too much money
Oh well, live and learn. When I'm done, I'm going to have one helluva harness
Oh well, live and learn. When I'm done, I'm going to have one helluva harness