Stock harness rewire questions - The 1947 - Present Chevrolet & GMC Truck Message Board Network

**kev2809** · 05-20-2022, 06:56 PM

engine is 2002 DBW 5.3/4l60e

im in the process of depinning the wires and removing everything i dont need. im using brendans chart on lt1swap.com...and so far have removed every yellow wire. my question is, what happens with the "tan" blocks on the chart? if if im using the 4l60e do i leave all the "red" blocks? and this might sound stupid, but the "blue" blocks stay in the pcm..but will eventually be wired to the stand alone fuseblock?

also, if i am not running electric fans, should i pull those pins too, or just wire them like i will use them just in case for future references?

and after snipping all the pink wires and orange wires in connector C2....i have a pink B9 wire that doesnt show in the diagram. does that get snipped too?

sorry to sound like an idiot, but i dont like wiring lol. i figured i would give this a shot to try it myself

87chevy.com · 05-21-2022, 09:38 PM

if the ecu is going to be in the engine bay, don't forget the ECU plugs to fit where the wire went. This keeps it water tight.
clint

aknovaman · 05-22-2022, 09:45 AM

I would like to suggest you use my spreadsheet to clarify and identify which wires are needed and those you can remove.
There is a tab for DBW
it's located here:

https://ls1tech.com/forums/conversio...m-pinouts.html

**kev2809** · 05-22-2022, 12:53 PM

so heres what i found this morning. that B9 goes to the tac module needed for the pedal, so that will be running to a fuse obviously. after pulling out the blue ones, i realized they obviously stay in the pcm connector. few of the pinks and oranges from there listed as blue, were previously cut and labeled from the big C2 connector.

as of now i have one pink wire that is labeled "pcm" i cut off from the C2 connector. it was originally 2 wires, one of them runs to the blue connector in pin 19. the other pink wire runs all the way back to where the trans plugs are at. that plug already has the other 3 wires pulled from the harness. im wondering why it was labeled "pcm" coming out of the C2 connector? does it just simply needs to be snipped and pulled? im thinking it was piggy backing off the blue 19 pin and is not actually needed?

**kev2809** · 05-22-2022, 12:55 PM

Quote:

Originally Posted by 87chevy.com

if the ecu is going to be in the engine bay, don't forget the ECU plugs to fit where the wire went. This keeps it water tight.
clint

yup, think i will stick some rtv or silicone in them. noticed they dont close back up after pulling a wire. thanks for the info

Quote:

Originally Posted by aknovaman

I would like to suggest you use my spreadsheet to clarify and identify which wires are needed and those you can remove.
There is a tab for DBW
it's located here:

https://ls1tech.com/forums/conversio...m-pinouts.html

thanks for the spreadsheet...i will look over it when i get back home. i hit a reply before looking over it!

**kev2809** · 05-22-2022, 10:17 PM

ok. after going through the rest of the wires heres where i am at. im left with the blue wires that go up to the tac module. after reading through the DBW section, those are for cruise control and are not needed. as i said above, i just need to connect the B9 pink wire to a fuse and the pedal should work.

i still dont know what that one pink wire goes to in the plug above that i had labeled "PCM". it was crimped to another pink wire in the C2 connector that i labeled "PCM" which ran to pin 19 in the blue connector. ill try to find some more info on it but im betting it gets deleted.

i left a few grounds sticking out for now to see if i will need them. the only other issue i had today was after reading through lt1swap.com was that he snipped all the wires on the trans plug except the black/white wire, including the pink. i traced that pink back to my bundle that was supposed to get fused and it was taped with "Trans PCM"

E2 - Fused Ignition Positive Voltage - Transmission, PCM

did i screw this part up? the rest of the wires from that trans plug were all already snipped for removal when i labeled the pink wires.

ls1nova71 · 05-23-2022, 07:34 AM

What transmission are you running? Usually you don't cut out the transmission wires. I'm guessing that plug in your pic is for the transfercase. Was your donor a 4x4?

**kev2809** · 05-23-2022, 08:07 AM

Quote:

Originally Posted by ls1nova71

What transmission are you running? Usually you don't cut out the transmission wires. I'm guessing that plug in your pic is for the transfercase. Was your donor a 4x4?

nope, believe truck was a 2wd. it didnt have any of the 4x4 wires listed in the pcm that gets pulled and it also didnt have the plug near the C connectors that have 4x4 wires.

that plug that i posted a picture of seems to run where my big trans plug is. its a 3 wire plug, 1 pink 1 white1 black. the black got snipped at a ground junction. after going through the yellow block pins to be pulled, there were only 2 that has a white wire to be pulled.

blue 56 - fuel temperature/composition signal (L59 flex fuel)

red 45 - EVAP canister vent valve control

**kev2809** · 05-23-2022, 08:09 AM

also, this is from lt1swaps's harness how to on their facebook regarding the trans plug.

https://www.facebook.com/lt1swap/pho...70184529682466

"On the 2 RANGE sensor plugs, the ONLY wire you need to keep on the larger plug is the BLACK/WHITE wire, remove the rest, and keep all 4 wires on the smaller plug."

**kev2809** · 05-23-2022, 09:57 AM

also, i didnt make it clear but im not talking about the big circle plug for the trans..its the smaller square connector. apparently the range selector plug? i found some good info on that selector plug and im guessing the wires from the square plug (including the pink that i have labeled " trans PCM") are if you are trying to use the black box off the side of the trans and not the neutral safety switch from the column? which is why its listed as removing.

https://ls1tech.com/forums/generatio...-question.html

still digging to see what that 3 wire plug is that runs in the same branch, but i also found this from lstech.

"Pin F2 in C2 should get wired to a 10A fuse that is ignition hot, pin E2 can get eliminated since you are getting power elsewhere."

pin E2 seems to be the wire that i labeled "trans PCM". so whatever that plug is..seems like it gets removed. that pink wire that goes to it is not needed since the trans is getting power through the pink wire labeled "trans solenoid" on F2? am i reading this right?

scroll to post 10
https://ls1tech.com/forums/conversio...ring-help.html

ls1nova71 · 05-23-2022, 09:51 PM

I just looked it up and that plug in the pic in post 4 is a fuel composition sensor plug. You shouldn't need it. Also, you don't need to really do anything to the range sensor plugs. Most of them just go from the plug straight to the PCM connector. If there's a pink ignition wire going to it, you won't need it either unless you are using it for a back up light switch or as a neutral safety switch.

**kev2809** · 05-23-2022, 10:31 PM

Quote:

Originally Posted by ls1nova71

I just looked it up and that plug in the pic in post 4 is a fuel composition sensor plug. You shouldn't need it. Also, you don't need to really do anything to the range sensor plugs. Most of them just go from the plug straight to the PCM connector. If there's a pink ignition wire going to it, you won't need it either unless you are using it for a back up light switch or as a neutral safety switch.

great! I'm guessing it was a flex fuel truck. I cleaned up a bit of the harness and removed the entire plug. I'm grouping the pink wires together now to simplify the fuse block so I'm sure I will have some questions.

do you happen to know if the harness purple starter wire is used or deleted? I see it labeled in just about every how to but nobody lists what they actually do with it?

ls1nova71 · 05-24-2022, 10:23 AM

The purple starter wire isn't terminated anywhere in the harness, it's just routed down to the starter with some other wires. If you look near where the original fuse box plugged into the harness you'll find the other end of it. You can either use it or delete it if you are using your original wiring. I like to use it because it's already there and it makes things cleaner, you just have to hook the other end to the original purple wire in the truck.

**kev2809** · 05-24-2022, 11:58 AM

Quote:

Originally Posted by ls1nova71

The purple starter wire isn't terminated anywhere in the harness, it's just routed down to the starter with some other wires. If you look near where the original fuse box plugged into the harness you'll find the other end of it. You can either use it or delete it if you are using your original wiring. I like to use it because it's already there and it makes things cleaner, you just have to hook the other end to the original purple wire in the truck.

right. it was snipped at the C2 connector I think. I wasn't sure if was controlled through the pcm or wiring to the truck harness starter wire. I'm using a universal 17 circuit harness for the truck which hasn't been installed yet.

I start fusing some of the pinks together following this diagram. but I'm changing it a little because I want them separated a bit more and not have too many linked to 1 fuse. so I bought a second fuse block

**kev2809** · 05-24-2022, 07:25 PM

quick question....for the diagram above, where would the pink 12v come from for the plug on the left? could I just split the pink 12v from any of the ones going to the fuse block? was thinking of splitting the pcm pink wire.

*edit* answered my own question. i just split the pcm #19 pin and ran one to the accessory bundle and the other to the fuse block.

**kev2809** · 05-29-2022, 01:51 PM

well, heres what i got. i drew a very terrible diagram that im hoping i can get someone to make me something official. i checked continuity on the fuse block to the 4 wires that run to the truck and they all check out. its getting taped up and loomed today so im hoping everything will check out when on the truck lol. i do still have the fan 1 and fan 2 not hooked up because for one..im unsure how to do it. but mainly, i dont have e fans and its not programmed in the pcm anyways. ill leave the wires in the loom for now and run them when/if i ever decide to run electric fans.

**kev2809** · 05-29-2022, 01:53 PM

and heres what i did the rest of the wires that run to the obd2, tach, tcc, etc. i wired them to a nifty little plug that, once i get this in the truck and get the truck wiring in, ill finish the other end of this plug and run them where they need to go.

87chevy.com · 06-04-2022, 06:22 PM

Quote:

Originally Posted by kev2809

yup, think i will stick some rtv or silicone in them. noticed they dont close back up after pulling a wire. thanks for the info

i have plenty extra from my builds... i can sell some to you if you rather do it the right way...
25Cents each plus 2 bucks usps.

**kev2809** · 06-04-2022, 06:56 PM

Quote:

Originally Posted by 87chevy.com

i have plenty extra from my builds... i can sell some to you if you rather do it the right way...
25Cents each plus 2 bucks usps.

thanks for the offer. I actually just squeezed some hot glue in the tiny holes left from the pulled wires.

05-21-2022, 09:38 PM	#2
87chevy.com BMW & ASE Master Certified Join Date: Feb 2004 Location: Houston, Texas Posts: 1,266	Re: Stock harness rewire questions if the ecu is going to be in the engine bay, don't forget the ECU plugs to fit where the wire went. This keeps it water tight. clint __________________ 1987 Silverado - L83 5.3 w/ 6L80e ,A/C,P/W,P/L,TILT, HID projectors, Wilwood C-10 Pro Spindles w/ 2018 silverado front brakes & C-5 Corvette Rear Disc Brakes 1999 BMW 528i - 5.7 LS1 w/ 4l60e, Ford 8.8 IRS w31 spline posi & FX-r projector retrofit New project: 2006 BMW x5 6cyl AWD to L83 6l80e 4wd to 2WD / RWD A poor man buy's it twice finally got my domain name back, 87chevy.com.... site rework in progress

05-22-2022, 09:45 AM	#3
aknovaman Registered User Join Date: Aug 2013 Location: Tecumseh Posts: 355	Re: Stock harness rewire questions I would like to suggest you use my spreadsheet to clarify and identify which wires are needed and those you can remove. There is a tab for DBW it's located here: https://ls1tech.com/forums/conversio...m-pinouts.html __________________ Current project 1959 Willys = GEZR TRUK Geezer is a Latin compound word made up of two roots. Gee meaning Urine Stain and Zer meaning your pants are open! FMCDH GBU and GBA http://www.youtube.com/user/aknovaman/videos Last edited by aknovaman; 05-22-2022 at 09:58 AM.

05-22-2022, 12:53 PM	#4
kev2809 low n' slo Join Date: Mar 2009 Location: rosenberg, texas Posts: 5,175	Re: Stock harness rewire questions so heres what i found this morning. that B9 goes to the tac module needed for the pedal, so that will be running to a fuse obviously. after pulling out the blue ones, i realized they obviously stay in the pcm connector. few of the pinks and oranges from there listed as blue, were previously cut and labeled from the big C2 connector. as of now i have one pink wire that is labeled "pcm" i cut off from the C2 connector. it was originally 2 wires, one of them runs to the blue connector in pin 19. the other pink wire runs all the way back to where the trans plugs are at. that plug already has the other 3 wires pulled from the harness. im wondering why it was labeled "pcm" coming out of the C2 connector? does it just simply needs to be snipped and pulled? im thinking it was piggy backing off the blue 19 pin and is not actually needed? Attached Images __________________ 67 1/2 ton Suburban - Project DRGNWGN. Build thread -_--_--_ _________ _--_-_ -/____\|__\|__\__ ,.,,,.,.,,.,\|_O _______ O_]

05-22-2022, 10:17 PM	#6
kev2809 low n' slo Join Date: Mar 2009 Location: rosenberg, texas Posts: 5,175	Re: Stock harness rewire questions ok. after going through the rest of the wires heres where i am at. im left with the blue wires that go up to the tac module. after reading through the DBW section, those are for cruise control and are not needed. as i said above, i just need to connect the B9 pink wire to a fuse and the pedal should work. i still dont know what that one pink wire goes to in the plug above that i had labeled "PCM". it was crimped to another pink wire in the C2 connector that i labeled "PCM" which ran to pin 19 in the blue connector. ill try to find some more info on it but im betting it gets deleted. i left a few grounds sticking out for now to see if i will need them. the only other issue i had today was after reading through lt1swap.com was that he snipped all the wires on the trans plug except the black/white wire, including the pink. i traced that pink back to my bundle that was supposed to get fused and it was taped with "Trans PCM" E2 - Fused Ignition Positive Voltage - Transmission, PCM did i screw this part up? the rest of the wires from that trans plug were all already snipped for removal when i labeled the pink wires. __________________ 67 1/2 ton Suburban - Project DRGNWGN. Build thread -_--_--_ _________ _--_-_ -/____\|__\|__\__ ,.,,,.,.,,.,\|_O _______ O_] Last edited by kev2809; 05-23-2022 at 12:59 PM.

05-23-2022, 07:34 AM	#7
ls1nova71 Registered User Join Date: Dec 2009 Location: Independence Mo Posts: 4,119	Re: Stock harness rewire questions What transmission are you running? Usually you don't cut out the transmission wires. I'm guessing that plug in your pic is for the transfercase. Was your donor a 4x4? __________________ My '72 short bed build. http://www.ls1tech.com/forums/conver...6-0-4l80e.html 5.3 swap into my RUSTY '71 C10 http://ls1tech.com/forums/conversion...71-c-10-a.html

05-20-2022, 06:56 PM	#1
kev2809 low n' slo Join Date: Mar 2009 Location: rosenberg, texas Posts: 5,175	Stock harness rewire questions engine is 2002 DBW 5.3/4l60e im in the process of depinning the wires and removing everything i dont need. im using brendans chart on lt1swap.com...and so far have removed every yellow wire. my question is, what happens with the "tan" blocks on the chart? if if im using the 4l60e do i leave all the "red" blocks? and this might sound stupid, but the "blue" blocks stay in the pcm..but will eventually be wired to the stand alone fuseblock? also, if i am not running electric fans, should i pull those pins too, or just wire them like i will use them just in case for future references? and after snipping all the pink wires and orange wires in connector C2....i have a pink B9 wire that doesnt show in the diagram. does that get snipped too? sorry to sound like an idiot, but i dont like wiring lol. i figured i would give this a shot to try it myself __________________ 67 1/2 ton Suburban - Project DRGNWGN. Build thread -_--_--_ _________ _--_-_ -/____\|__\|__\__ ,.,,,.,.,,.,\|_O _______ O_]

05-23-2022, 08:09 AM	#9
kev2809 low n' slo Join Date: Mar 2009 Location: rosenberg, texas Posts: 5,175	Re: Stock harness rewire questions also, this is from lt1swaps's harness how to on their facebook regarding the trans plug. https://www.facebook.com/lt1swap/pho...70184529682466 "On the 2 RANGE sensor plugs, the ONLY wire you need to keep on the larger plug is the BLACK/WHITE wire, remove the rest, and keep all 4 wires on the smaller plug." Attached Images __________________ 67 1/2 ton Suburban - Project DRGNWGN. Build thread -_--_--_ _________ _--_-_ -/____\|__\|__\__ ,.,,,.,.,,.,\|_O _______ O_]

05-23-2022, 09:57 AM	#10
kev2809 low n' slo Join Date: Mar 2009 Location: rosenberg, texas Posts: 5,175	Re: Stock harness rewire questions also, i didnt make it clear but im not talking about the big circle plug for the trans..its the smaller square connector. apparently the range selector plug? i found some good info on that selector plug and im guessing the wires from the square plug (including the pink that i have labeled " trans PCM") are if you are trying to use the black box off the side of the trans and not the neutral safety switch from the column? which is why its listed as removing. https://ls1tech.com/forums/generatio...-question.html still digging to see what that 3 wire plug is that runs in the same branch, but i also found this from lstech. "Pin F2 in C2 should get wired to a 10A fuse that is ignition hot, pin E2 can get eliminated since you are getting power elsewhere." pin E2 seems to be the wire that i labeled "trans PCM". so whatever that plug is..seems like it gets removed. that pink wire that goes to it is not needed since the trans is getting power through the pink wire labeled "trans solenoid" on F2? am i reading this right? scroll to post 10 https://ls1tech.com/forums/conversio...ring-help.html __________________ 67 1/2 ton Suburban - Project DRGNWGN. Build thread -_--_--_ _________ _--_-_ -/____\|__\|__\__ ,.,,,.,.,,.,\|_O _______ O_] Last edited by kev2809; 05-23-2022 at 10:12 AM.

05-23-2022, 09:51 PM	#11
ls1nova71 Registered User Join Date: Dec 2009 Location: Independence Mo Posts: 4,119	Re: Stock harness rewire questions I just looked it up and that plug in the pic in post 4 is a fuel composition sensor plug. You shouldn't need it. Also, you don't need to really do anything to the range sensor plugs. Most of them just go from the plug straight to the PCM connector. If there's a pink ignition wire going to it, you won't need it either unless you are using it for a back up light switch or as a neutral safety switch. __________________ My '72 short bed build. http://www.ls1tech.com/forums/conver...6-0-4l80e.html 5.3 swap into my RUSTY '71 C10 http://ls1tech.com/forums/conversion...71-c-10-a.html

05-24-2022, 10:23 AM	#13
ls1nova71 Registered User Join Date: Dec 2009 Location: Independence Mo Posts: 4,119	Re: Stock harness rewire questions The purple starter wire isn't terminated anywhere in the harness, it's just routed down to the starter with some other wires. If you look near where the original fuse box plugged into the harness you'll find the other end of it. You can either use it or delete it if you are using your original wiring. I like to use it because it's already there and it makes things cleaner, you just have to hook the other end to the original purple wire in the truck. __________________ My '72 short bed build. http://www.ls1tech.com/forums/conver...6-0-4l80e.html 5.3 swap into my RUSTY '71 C10 http://ls1tech.com/forums/conversion...71-c-10-a.html

05-24-2022, 07:25 PM	#15
kev2809 low n' slo Join Date: Mar 2009 Location: rosenberg, texas Posts: 5,175	Re: Stock harness rewire questions quick question....for the diagram above, where would the pink 12v come from for the plug on the left? could I just split the pink 12v from any of the ones going to the fuse block? was thinking of splitting the pcm pink wire. edit answered my own question. i just split the pcm #19 pin and ran one to the accessory bundle and the other to the fuse block. __________________ 67 1/2 ton Suburban - Project DRGNWGN. Build thread -_--_--_ _________ _--_-_ -/____\|__\|__\__ ,.,,,.,.,,.,\|_O _______ O_] Last edited by kev2809; 05-25-2022 at 02:44 PM.

05-29-2022, 01:51 PM	#16
kev2809 low n' slo Join Date: Mar 2009 Location: rosenberg, texas Posts: 5,175	Re: Stock harness rewire questions well, heres what i got. i drew a very terrible diagram that im hoping i can get someone to make me something official. i checked continuity on the fuse block to the 4 wires that run to the truck and they all check out. its getting taped up and loomed today so im hoping everything will check out when on the truck lol. i do still have the fan 1 and fan 2 not hooked up because for one..im unsure how to do it. but mainly, i dont have e fans and its not programmed in the pcm anyways. ill leave the wires in the loom for now and run them when/if i ever decide to run electric fans. Attached Images __________________ 67 1/2 ton Suburban - Project DRGNWGN. Build thread -_--_--_ _________ _--_-_ -/____\|__\|__\__ ,.,,,.,.,,.,\|_O _______ O_]

05-29-2022, 01:53 PM	#17
kev2809 low n' slo Join Date: Mar 2009 Location: rosenberg, texas Posts: 5,175	Re: Stock harness rewire questions and heres what i did the rest of the wires that run to the obd2, tach, tcc, etc. i wired them to a nifty little plug that, once i get this in the truck and get the truck wiring in, ill finish the other end of this plug and run them where they need to go. Attached Images __________________ 67 1/2 ton Suburban - Project DRGNWGN. Build thread -_--_--_ _________ _--_-_ -/____\|__\|__\__ ,.,,,.,.,,.,\|_O _______ O_]



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