four fuses and two relays. need help. - The 1947 - Present Chevrolet & GMC Truck Message Board Network

handyhands · 03-22-2022, 05:53 PM

Hey all, i haven't posted in a long time. my 4 fuse block has full power without key on. i dont think this is right. when i turn (to the on position) the key nothing happens. i used lt1 swap for the fuses and relays. even the fuel pump runs for 2-3 seconds when i connect the battery ground.
2002 5.3 DBW

handyhands · 03-22-2022, 06:57 PM

this is a 1953 ad, s10 swap. s10 wiring from cab.

**CarlsLQ9SS** · 03-23-2022, 06:36 AM

It sounds like you have battery power to the ignition wire that goes to the ignition relay.

handyhands · 03-26-2022, 08:11 PM

ok it's still not right. i removed the constant wire going to the cab. put a constant wire to feed harness only. still have the same problem. dose this mean i have wire something wrong in the harness?

ls1nova71 · 03-27-2022, 11:04 AM

Yes, you have something wired wrong. There should be a constant hot and an ignition (key on) hot to the ignition relay. It sounds like that isn't hooked up right. What wire are you using to power up the relay?

**Richard** · 03-28-2022, 12:00 AM

Ditto to the two previous posts. Check to see if you hear the relays click when you connect battery ground. Constant +12v should go to common terminal on relays. Switched +12v power should be going to the coil on relay. The wire on the coil of relay should not have power when ignition is off.

handyhands · 03-28-2022, 04:28 PM

i have a constant hot from the battery to power relay and PCM. keyed pink wire hot in start and run for relay. without turning the key all fuses have power. yes i hear the relays and fuel pump for around 2-3 seconds. I followed ucandoit site to wire relays and changed it to lt1 swap with the same result.

handyhands · 03-28-2022, 04:45 PM

pink wire is only hot with key on.

handyhands · 03-29-2022, 06:26 PM

ok, with constant hot wire i am getting power to the fuses thru what is suppose to be injector wires.

ls1nova71 · 03-29-2022, 10:18 PM

If you have constant power on the injector wires, then you're probably back-feeding power to the whole harness. You don't have something wired right. Have you pulled the relay to see if the constant power goes away?

handyhands · 03-30-2022, 05:55 PM

i tried removing the relay today, still have constant power. looks like i am going to take the harness off and see what i can find.

handyhands · 04-11-2022, 05:06 PM

thanks everyone for your help. I found the back feed in the harness. everything looks to be right now and harness is back on the motor. Next will be checking fuel lines and cleaning up a few wires.

**kev2809** · 04-19-2022, 04:16 PM

quick question. you only used lt1swap for their diagram, or were they the ones that actually rewired it for you?

Nima · 04-20-2022, 11:13 PM

I am glad you found the problem.
Based on what you have explained, I thought you wiring to the main relay (relay's posts) may have been mixed up. You may want to check on that if you have not already.
Good luck.

handyhands · 04-21-2022, 08:49 AM

I used lt1swap diagram . He did my computer.

**kev2809** · 04-22-2022, 08:43 AM

Quote:

Originally Posted by handyhands

I used lt1swap diagram . He did my computer.

ah OK. ya I plan to send them the computer as well, just wondering if I should rewire myself or send them mine to rewire.

03-22-2022, 05:53 PM	#1
handyhands Registered User Join Date: Mar 2011 Location: madison, NC Posts: 81	four fuses and two relays. need help. Hey all, i haven't posted in a long time. my 4 fuse block has full power without key on. i dont think this is right. when i turn (to the on position) the key nothing happens. i used lt1 swap for the fuses and relays. even the fuel pump runs for 2-3 seconds when i connect the battery ground. 2002 5.3 DBW

03-22-2022, 06:57 PM	#2
handyhands Registered User Join Date: Mar 2011 Location: madison, NC Posts: 81	Re: four fuses and two relays. need help. this is a 1953 ad, s10 swap. s10 wiring from cab.

03-23-2022, 06:36 AM	#3
CarlsLQ9SS Senior Member Join Date: Aug 2018 Location: London, Ky Posts: 1,163	Re: four fuses and two relays. need help. It sounds like you have battery power to the ignition wire that goes to the ignition relay. __________________ Carl 1971 GMC short bed, (Henry) Options I've added, tilt, ac, 8k tach, Electric speedometer conversion for LS swap, 6.0 with 823 heads and BTR stage 4 truck cam, 4L80e, posi with 3.73 rear end, Power steering and power brakes Lowered 5/7. Frame up build.

03-26-2022, 08:11 PM	#4
handyhands Registered User Join Date: Mar 2011 Location: madison, NC Posts: 81	Re: four fuses and two relays. need help. ok it's still not right. i removed the constant wire going to the cab. put a constant wire to feed harness only. still have the same problem. dose this mean i have wire something wrong in the harness?

03-27-2022, 11:04 AM	#5
ls1nova71 Registered User Join Date: Dec 2009 Location: Independence Mo Posts: 4,119	Re: four fuses and two relays. need help. Yes, you have something wired wrong. There should be a constant hot and an ignition (key on) hot to the ignition relay. It sounds like that isn't hooked up right. What wire are you using to power up the relay? __________________ 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

03-28-2022, 12:00 AM	#6
Richard Senior Member Join Date: Dec 1999 Location: Southern California Posts: 2,884	Re: four fuses and two relays. need help. Ditto to the two previous posts. Check to see if you hear the relays click when you connect battery ground. Constant +12v should go to common terminal on relays. Switched +12v power should be going to the coil on relay. The wire on the coil of relay should not have power when ignition is off. __________________ Richard 1972 K10 Custom Deluxe SWB Fleetside My build https://67-72chevytrucks.com/vboard/...d.php?t=800746

03-28-2022, 04:28 PM	#7
handyhands Registered User Join Date: Mar 2011 Location: madison, NC Posts: 81	Re: four fuses and two relays. need help. i have a constant hot from the battery to power relay and PCM. keyed pink wire hot in start and run for relay. without turning the key all fuses have power. yes i hear the relays and fuel pump for around 2-3 seconds. I followed ucandoit site to wire relays and changed it to lt1 swap with the same result.

03-28-2022, 04:45 PM	#8
handyhands Registered User Join Date: Mar 2011 Location: madison, NC Posts: 81	Re: four fuses and two relays. need help. pink wire is only hot with key on.

03-29-2022, 06:26 PM	#9
handyhands Registered User Join Date: Mar 2011 Location: madison, NC Posts: 81	Re: four fuses and two relays. need help. ok, with constant hot wire i am getting power to the fuses thru what is suppose to be injector wires.

03-29-2022, 10:18 PM	#10
ls1nova71 Registered User Join Date: Dec 2009 Location: Independence Mo Posts: 4,119	Re: four fuses and two relays. need help. If you have constant power on the injector wires, then you're probably back-feeding power to the whole harness. You don't have something wired right. Have you pulled the relay to see if the constant power goes away? __________________ 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

03-30-2022, 05:55 PM	#11
handyhands Registered User Join Date: Mar 2011 Location: madison, NC Posts: 81	Re: four fuses and two relays. need help. i tried removing the relay today, still have constant power. looks like i am going to take the harness off and see what i can find.

04-11-2022, 05:06 PM	#12
handyhands Registered User Join Date: Mar 2011 Location: madison, NC Posts: 81	Re: four fuses and two relays. need help. thanks everyone for your help. I found the back feed in the harness. everything looks to be right now and harness is back on the motor. Next will be checking fuel lines and cleaning up a few wires.

04-19-2022, 04:16 PM	#13
kev2809 low n' slo Join Date: Mar 2009 Location: rosenberg, texas Posts: 5,175	Re: four fuses and two relays. need help. quick question. you only used lt1swap for their diagram, or were they the ones that actually rewired it for you? __________________ 67 1/2 ton Suburban - Project DRGNWGN. Build thread -_--_--_ _________ _--_-_ -/____\|__\|__\__ ,.,,,.,.,,.,\|_O _______ O_]

04-20-2022, 11:13 PM	#14
Nima Blue 67 Join Date: Apr 2004 Location: Western WA Posts: 1,179	Re: four fuses and two relays. need help. I am glad you found the problem. Based on what you have explained, I thought you wiring to the main relay (relay's posts) may have been mixed up. You may want to check on that if you have not already. Good luck. __________________ 1953 GMC 3/4 ton: current project 1967 C20: 5.3 voretc with T5 conversion, 4 wheel 8 lug disc brake 1972 Nova: my 4 door sport sedan! 5.3 voretc + T5 conversion. drivable project, FUN!! 1979 Camaro Z28: 5.3 vortec conversion with build TH350: drivable project, Fun to drive 1992 Camaro RS convertible (Z28 clone): 5.3 conversion with build T5: on going project 2005 Silverado 2500, 4x4 Duramax, original owner

04-21-2022, 08:49 AM	#15
handyhands Registered User Join Date: Mar 2011 Location: madison, NC Posts: 81	Re: four fuses and two relays. need help. I used lt1swap diagram . He did my computer.



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