Help With Wiring Harness On Conversion
Help With Wiring Harness On Conversion **mods if this is in the wrong forum-please move it, thanks!**
I'm in the process of getting everything together to make the conversion on my '02 Silverado from 4.3/Manual 5 spd, to 5.3L/4L60E.
I'm in desperate need of a complete wiring harness. My buddy just parted out a 2005 Suburban and gave me the entire wiring harness, computer, and fuse panel, from that vehicle. It was a 5.3L/4L60E. I'm being told that this harness/computer will not work.
I'm wondering can any portion of this harness be used, or converted for use?
Am I correct in thinking that the automatic trans portion where it bolts to the bottom of the fuse panel can be used? If I were to cut off the main connectors where it plugs into the computer, could I then just use the RED & BLUE connectors from the harness in the truck and make all of the wires connect in the proper location?
If I can't use/convert this harness-does anyone know where I can find a used GM harness? Any books out there on modifying harnesses for these types of conversions?
I'm in the process of getting everything together to make the conversion on my '02 Silverado from 4.3/Manual 5 spd, to 5.3L/4L60E.
I'm in desperate need of a complete wiring harness. My buddy just parted out a 2005 Suburban and gave me the entire wiring harness, computer, and fuse panel, from that vehicle. It was a 5.3L/4L60E. I'm being told that this harness/computer will not work.
I'm wondering can any portion of this harness be used, or converted for use?
Am I correct in thinking that the automatic trans portion where it bolts to the bottom of the fuse panel can be used? If I were to cut off the main connectors where it plugs into the computer, could I then just use the RED & BLUE connectors from the harness in the truck and make all of the wires connect in the proper location?
If I can't use/convert this harness-does anyone know where I can find a used GM harness? Any books out there on modifying harnesses for these types of conversions?
Well it is possible but here are some general things to consider . What year is engine and trans ? You said you have red/blue connectors that would be 99-02 . But the harness you have is 2005 is that right.
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Thanks for the replies guys.. My truck is an '02 and the harness/computer/fuse panel is from a 2005.
I started tearing the '05 harness apart today. I removed all pins from the 2 main connectors for the computer and I am unraveling every bit of it.
I started by just trying to remove the transmission section of the harness from the rest of the harness, but grounds tie it to other sections and I don't want to cut the grounds for now.
My thinking was if I can separate the big harness into several smaller harnesses it will be much easier to manage.
If I really think this through I should only have to add wires for the individual coils, extra wires for the 2 extra fuel injectors, and some others I have not thought about yet. It would be SO much easier if he had marked what the different connectors attached to BEFORE he pulled the harness. I got the harness (all 45 lbs of it!) just rolled up in a box. The good news is that the only cut wire I have found so far is the purple wire that goes to the starter solenoid-which I won't be using anyway!
Since I'm not sure what the various connectors attach to, it's hard to figure out which ones I can eliminate, and which ones to keep. I do plan on just re-routing, or extending wires, that are already present in the engine bay on the existing motor. The current 4.3 has a crank position sensor so I'll just reroute that connector onto the 5.3L-hopefully the connector is the same? I'll re-use the wires running to the current starter, the cam position sensor, oil level position, knock sensors, etc;
This is where I am going to get into trouble is if I don't have the proper connectors for the various items. Buying the correct pig-tails could add up quickly.
The good news is that I will have plenty of the pins for re-pinning the computer that is already in the truck! The other issue I see is that the '05 harness is DBW and my 5.3L motor is DBC.. Should I just convert over to DBW since it would only mean I need the accelerator pedal, and the correct throttle body? Any inherent advantages to having DBW over DBC? I'd think it's one less thing to go bad to just stay with cable. I'm rambling so I'll end here.
Heading back out to the shop to continue disassembly of this crazy harness.
I started tearing the '05 harness apart today. I removed all pins from the 2 main connectors for the computer and I am unraveling every bit of it.
I started by just trying to remove the transmission section of the harness from the rest of the harness, but grounds tie it to other sections and I don't want to cut the grounds for now.
My thinking was if I can separate the big harness into several smaller harnesses it will be much easier to manage.
If I really think this through I should only have to add wires for the individual coils, extra wires for the 2 extra fuel injectors, and some others I have not thought about yet. It would be SO much easier if he had marked what the different connectors attached to BEFORE he pulled the harness. I got the harness (all 45 lbs of it!) just rolled up in a box. The good news is that the only cut wire I have found so far is the purple wire that goes to the starter solenoid-which I won't be using anyway!
Since I'm not sure what the various connectors attach to, it's hard to figure out which ones I can eliminate, and which ones to keep. I do plan on just re-routing, or extending wires, that are already present in the engine bay on the existing motor. The current 4.3 has a crank position sensor so I'll just reroute that connector onto the 5.3L-hopefully the connector is the same? I'll re-use the wires running to the current starter, the cam position sensor, oil level position, knock sensors, etc;
This is where I am going to get into trouble is if I don't have the proper connectors for the various items. Buying the correct pig-tails could add up quickly.
The good news is that I will have plenty of the pins for re-pinning the computer that is already in the truck! The other issue I see is that the '05 harness is DBW and my 5.3L motor is DBC.. Should I just convert over to DBW since it would only mean I need the accelerator pedal, and the correct throttle body? Any inherent advantages to having DBW over DBC? I'd think it's one less thing to go bad to just stay with cable. I'm rambling so I'll end here.
Heading back out to the shop to continue disassembly of this crazy harness.
Got the harness torn apart and separated into smaller harnesses. Currently have the trans harness (main trans connector, neutral safety switch, speed sensor, and rear O2 sensor), passenger side coil/injector harness w/cam position & oil pressure, and then I have the drivers bank of injectors (still looking for the plug for the coil pack on that side), and several as yet unidentified connectors. I will need to lay the chopped harness on top of the motor and start mapping out where everything attaches.
I do plan on running the harness to the back of the motor and across the firewall as opposed to the way GM runs it on the trucks which is right over the exhaust on drivers side and then right on top of the middle of the engine. I am running the harness to the back of the motor also because I will be putting that new Dorman LS2 intake on as soon as it comes out!
Random observations: GM must have a reason for putting all 4 injectors inside the same loom on the passenger side, but then only putting 3 injectors in 1 loom on the drivers side, and leaving the 4th as part of another harness. Weird. I plan on putting them ALL together at the back of the engine in 1 harness. Also, the pink wires.... So many pink wires! I guess GM thought that if 1 pink wire grounded out and blew a fuse, it would be better than having them all bundled together and then if it blew a fuse the entire engine would shut down. At least this is why I think GM made so many individual power wires running back to the distribution block.
It will take some time to get it all sorted out, but it's just taking step by step and eventually I will get there. After this, I think it will be easier to make the next harness. Especially if I start with the correct YEAR I'm working on.
I do plan on running the harness to the back of the motor and across the firewall as opposed to the way GM runs it on the trucks which is right over the exhaust on drivers side and then right on top of the middle of the engine. I am running the harness to the back of the motor also because I will be putting that new Dorman LS2 intake on as soon as it comes out!
Random observations: GM must have a reason for putting all 4 injectors inside the same loom on the passenger side, but then only putting 3 injectors in 1 loom on the drivers side, and leaving the 4th as part of another harness. Weird. I plan on putting them ALL together at the back of the engine in 1 harness. Also, the pink wires.... So many pink wires! I guess GM thought that if 1 pink wire grounded out and blew a fuse, it would be better than having them all bundled together and then if it blew a fuse the entire engine would shut down. At least this is why I think GM made so many individual power wires running back to the distribution block.
It will take some time to get it all sorted out, but it's just taking step by step and eventually I will get there. After this, I think it will be easier to make the next harness. Especially if I start with the correct YEAR I'm working on.
