Electrical help with swap please.
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From: San Marcos, Tx
Electrical help with swap please. I sent an Email to Brendan at LT1SWAP.com and am waiting for a reply. But someone here may know as well.
I have a thread going on my swap. 97 S10 getting a 2002 LQ4 and 4L80 trany.
Brendan programmed the ecm and I used his website to clean up the harness for the swap. What I am looking for is what wires from the truck hook up to which wires in the engine harness for things on the dash and ignition. So oil pressure, voltage, water temp, speedo and ignition. And anything else that I would hook up. I'll admit that electrical does frustrate me a little.
Thanks for the info.
I have a thread going on my swap. 97 S10 getting a 2002 LQ4 and 4L80 trany.
Brendan programmed the ecm and I used his website to clean up the harness for the swap. What I am looking for is what wires from the truck hook up to which wires in the engine harness for things on the dash and ignition. So oil pressure, voltage, water temp, speedo and ignition. And anything else that I would hook up. I'll admit that electrical does frustrate me a little.
Thanks for the info.
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From: alburnett, iowa
I made a panel to hold aftermarket guages in my stock speedo location. water temp, charging, oil pressure, electric speedo all hook up no problem. speedo goes to the vss wire. The other wires either has 12v from battery or hook up to keyed run position 12v. Brendan has in chart for the power wires on which way need connected for power. You also need to run ground and hot for fuel pump to its location. Power for it comes out of fuel pump relay you wired with the fuse panel you put together. Im not sure but you mite be able to run sending units from your original truck set up with wires out of factory harness and figure out speedometer wire as well. see if someone in S-10 area knows.
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I thought about the aftermarket gauges in a built dash. Brendan set me up so the speedo will work. I just don't know how to get the LQ4 engine sensors to communicate with the S10 dash so the other stuff works. even the ignition wire is an unknown for me right now. I know it needs to be hooked up to the fuse/relay panel I bought for the conversion, but I don't know which wire it is. Same for the fuel pump. Which wire from the harness plug at the stock firewall controls these items?
I looked at the wiring detail sheet on his website, but it doesn't specify my exact truck and what wire it would be. Again, I am not real good with electrical. The race cars I built were easy. No Computers to mess with.
I looked at the wiring detail sheet on his website, but it doesn't specify my exact truck and what wire it would be. Again, I am not real good with electrical. The race cars I built were easy. No Computers to mess with.
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From: alburnett, iowa
Do you still have factory wires for original engine? If do use your stock sensors for the s-10 put them on motor. Fitting holes are metric on Ls motor(adapters are on ebay $28.00) screw them in so they should work. Fuel pump I would make a ground wire run to pump from where grounds are on engine. Fuel pump hot wire is coming out of the relay you wired in when doing fuse panel. Run it to where you stopped at pump connect it as well with ground. Your not going to use factory fuel pump circuit pull the original fuse box fuel pump fuse dont need it anymore. Find a hot 12v on/off key that stays hot while cranking over hook that to your wire to fuse panel you already wired. You can use 1 of wires that originally went to altenator as it on/off key.
Last edited by 76larkman; Dec 26, 2014 at 10:05 AM.
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From: San Marcos, Tx
Sold the engine out of the truck and the sensors went with it. So for water temp, oil pressure and volts. The ECM doesn't need to read any of this? I don't remember what connectors the harness had on it.
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From: alburnett, iowa
at this point I probably go aftermarket guages and panel. make the panel ok on your own. I got a guage set for $265 from speedway. Still had to buy adapters for oil/temp guages (28 on ebay)guege senders are standard motor holes metric. electric speedo hook up be easier. This would probably be easier for you as you done for stock cars. Starter can use s-10 wiring and will need to hook stud back altenator tp positive battery so you will charge.
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From: San Marcos, Tx
OK, an update. Went with aftermarket gauges for oil pressure and water temp. Also installed a fuel pressure gauge in front of the windshield. The ecm does hook up to the stock water temp in the head. So I have to locate another spot for my added gauge.
I have the ecm wired except for the following,
TCC
Speedo
Tach
ignition/run
start signal
So what I have been trying to get done today is the start and run. I haven't been able to fin ANY wiring schematics to really tell me what the wire colors are. I found one forum that I think I figured everything out on.
I know yellow is the start.
I have 2 reds for 12v
orange is accessories
pink is ignition
But I also have a brown wire. Not sure what this one does.
So here is what I found so far for the yellow start wire.
When I turn the key to the ON position, all wires get 12 volts except the yellow. It has 10 volts. Not sure why it has ANY voltage since its the start signal only.
My question is why does the yellow wire have 10 volts when not in the start position? Is this normal? I want to hook this up to my start signal wire at the relay/fuse block but am afraid that the starter will not get released if the relay/fuse block sees the small 10volt signal. Is there a start relay that's on the truck that I need to get my start signal after? Or do I get it straight from the ignition switch?
And I am pretty sure the Pink wire goes straight to the ignition/run wire on the fuse/relay block.
FYI, I bought the prebuilt fuse/relay setup from Current performance. That way you know what I am working with.
Thanks for any help.
I have the ecm wired except for the following,
TCC
Speedo
Tach
ignition/run
start signal
So what I have been trying to get done today is the start and run. I haven't been able to fin ANY wiring schematics to really tell me what the wire colors are. I found one forum that I think I figured everything out on.
I know yellow is the start.
I have 2 reds for 12v
orange is accessories
pink is ignition
But I also have a brown wire. Not sure what this one does.
So here is what I found so far for the yellow start wire.
When I turn the key to the ON position, all wires get 12 volts except the yellow. It has 10 volts. Not sure why it has ANY voltage since its the start signal only.
My question is why does the yellow wire have 10 volts when not in the start position? Is this normal? I want to hook this up to my start signal wire at the relay/fuse block but am afraid that the starter will not get released if the relay/fuse block sees the small 10volt signal. Is there a start relay that's on the truck that I need to get my start signal after? Or do I get it straight from the ignition switch?
And I am pretty sure the Pink wire goes straight to the ignition/run wire on the fuse/relay block.
FYI, I bought the prebuilt fuse/relay setup from Current performance. That way you know what I am working with.
Thanks for any help.
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From: alburnett, iowa
TCC goes onto a brake switch at brake pedal saw somewhere on here about diagram sometime ago. your speedo I think you can pick that up at original pcm connector or take dash apart trace it on back of cluster. TACh original coil had hook up I believe if you still have factory engine harness on it yet. Starter I believe is the brown your wandering about I think. Is it out of factory harness? My original starter wiring worked out same just deleted the fat purple on truck harness I used. most all pink wires go on engine start/run with key with 10 amp fuses. as well it should be injectors, o2 sensors, computor with key, ignition coils & mass air flo sensor. your altenator should go to pcm to activate and stud on back to battery. Should be 2 orange from pcm plug goes to battery 12v supply constant power. I put those on 10 amp fuse for protection. Im not up on your box you bought, whats it have for info with it? Passenger head by exhaust has a plug you can do guage with but its metric. you need an adaptor or drill hole in water pump and tap is what most is doing.
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http://www.currentperformance.com/sh...erelay-module/
This is the fuse/relay box I bought. Pretty nice really.
I have everything hooked up except the few wires. I need to check my brake switch for the correct wiring of the TCC. I think it needs to have constant 12v when the brake is not applied. So loss of 12volts releases the converter. And I will locate the speedo wire when I get the start and run thing figured out first. The tach wire will go to an aftermarket tach.
I have a Haynes manual, which really sucks that states the yellow wire if the start wire from the key. "its the only wire shown on the key switch btw" My problem is that this yellow wire has 10volts on it before I go to the start position on the switch. This will probably signal the starter before I go to the start position. And all other wires have 12 volts when in the run position. So the yellow has to be the correct wire but the 10volts has me confused.
And then I am pretty sure the pink wire goes to the run wire.
This is the fuse/relay box I bought. Pretty nice really.
I have everything hooked up except the few wires. I need to check my brake switch for the correct wiring of the TCC. I think it needs to have constant 12v when the brake is not applied. So loss of 12volts releases the converter. And I will locate the speedo wire when I get the start and run thing figured out first. The tach wire will go to an aftermarket tach.
I have a Haynes manual, which really sucks that states the yellow wire if the start wire from the key. "its the only wire shown on the key switch btw" My problem is that this yellow wire has 10volts on it before I go to the start position on the switch. This will probably signal the starter before I go to the start position. And all other wires have 12 volts when in the run position. So the yellow has to be the correct wire but the 10volts has me confused.
And then I am pretty sure the pink wire goes to the run wire.
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From: alburnett, iowa
I think I would call or email company on yellow wire as Im not sure either. I would think it would be 12v with key hold over for S-wire on starter. Otherwise not hot. are all your pinks then hot key on/run off otherwise? sounds like you bout got it figured out.
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Red wires hot all the time
Yellow wire 10v in run position, then 12v in start position
All others are 12v in run.
Just the yellow having any voltage at all when in run has me confused.
Yellow wire 10v in run position, then 12v in start position
All others are 12v in run.
Just the yellow having any voltage at all when in run has me confused.
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From: alburnett, iowa
if its on a relay, change out relay with another see what happens. It should have no power other than with key in cranking position. You could go to ignition swith and find the hot wire only in cronk hold over position. that would work for starter S-terminal. just not use yellow wire.
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Well I used the yellow wire after a test It doesn't kick the relay until the key is in start position. So I have it starting with the ignition switch now. Seems to work fine. Still going to investigate the small voltage on the yellow wire. Used the pink wire for run.
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Yea, that's happens a lot with me. I sit there looking at it, trying to figure out something, get stuck and give up. Come into the house and it hits me while I am watching TV. I guess as K says, "sometimes you just need some pie"