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Old 04-05-2009, 03:57 AM   #1
rage777
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ez wiring harness questions

i'm installing an ez wiring harness and while their instructions are decent, i have a hard time getting a hold of their tech support.

has anyone done one of these? do i need to install inline fuses like on the stock harness? they don't mention them in the instructions. can anyone help me out with this?

the old harness was a mess. i'm not sure what wire(s) i need to connect to HEI.
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Old 04-05-2009, 11:26 AM   #2
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Re: ez wiring harness questions

If your refering to the inline fuses for the ammeter, yes the fuses are there to protect the ammeter. For the HEI all you need is a ign sourced non resistance power source with full batt voltage.
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Old 04-05-2009, 02:29 PM   #3
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Re: ez wiring harness questions

the harness has a wire for the coil. i assume then that it is wired for a stock distributor? do i connect the tach wire to the same batt. connection on HEI?

what about the backup power and backup light? i have no idea what that's for. same with the brake switch.
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Old 04-05-2009, 07:20 PM   #4
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Re: ez wiring harness questions

If the wire labeled coil has full batt voltage it can go to the batt term on the hei. The tach terminal is only if you have a tach otherwise it's not needed to opperate. Back up power is fused supply going to your back up sw. and backup light goes to the other side of the backup switch and completes the circuit to the lights
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Old 04-05-2009, 11:46 PM   #5
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Re: ez wiring harness questions

i figured out the brake switch and backup switch today. so the coil wire and tach wire go to the HEI batt. term.? does anything hook up to the coil term. on HEI? i found the neutral safety but it was disconnected. i'm a little confused on how that gets hooked up. i've read that some guys say you don't have to have it.
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Old 04-06-2009, 01:53 AM   #6
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Re: ez wiring harness questions

The wire labeled coil should go to the batt terminal on the HEI dizzy but make certain that there is no resistance and delivers full batt voltage. The tach wire should go to the tach terminal on the dizzy not needed if you dont have a tach (that terminal if grounded prevents spark). there should be no other wires needed for the dizzy. The neutral safety switch is wired in series with the wire running from the ign sw run position to the starter (auto trans only)
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Old 04-06-2009, 09:41 PM   #7
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Re: ez wiring harness questions

in connecting the gauge harness i noticed there's no oil send on the harness. where does the oil send connect to then? and the fuel gauge feed is what the gauge power connects to? what connects to the brake warn lamp? there are 2 wires on the harness. i think 1 goes to the master cylinder. and the other?

i'm also unsure about the dome lamp. the lamp has an orange and a white but the ez harness only has the white power.

i'm using this diagram for the gauge harness.

sorry for all the questions. i'm trying to get this right without any screwups.
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Old 04-06-2009, 09:46 PM   #8
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Re: ez wiring harness questions

here's the diagram for the gauge connections.
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Old 04-06-2009, 11:25 PM   #9
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Re: ez wiring harness questions

i realized that the oil send on my gauge is mechanical not electrical. so that's figured out. i want to use the d---c volt meter gauge in my dash. do i need to hook that up as if it were the ammeter? or just the gauge harness connections and the solenoid power straight to the solenoid? these are really my last important connections. after that it's just the turn signal switch. i had no idea this would suck this bad and be so confusing. thanks again.
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Old 04-07-2009, 12:08 AM   #10
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Re: ez wiring harness questions

The voltmeter gauge you are refering to is that the stock ammeter or an aftermarket volt meter if it's a actual voltmeter just hook it up to sw. ign and ground but if it's the stock ammeter it's connected parallel to the charge wire from the alt to the batt
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Old 04-07-2009, 12:45 PM   #11
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Re: ez wiring harness questions

i've decided not to hook up the stock ammeter. will i still need to run the wires from the gauge harness to the alternator and battery? i have been warned that with the 70 amp alt. i'm installing that it could potentially start fires.

then there's the brake warning light. one wire goes to the master cyl. where does the other wire go? i was told i should connect to a keyed switch connection. to the ign. or what?
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Old 04-07-2009, 01:14 PM   #12
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Re: ez wiring harness questions

The stock ammeter is an external shunt type and no risk of fire regarless of alt output basically the way it's wired is one of the ammeter wires connect to the mains buss where the 8ga charge wire runs to the battery and the other wire connects at the other end of that wire (that 8 ga charge wire is the shunt) and the ammeter reads according to the voltage drop at either end of that wire very little current runs to the ammeter thats why they use 4 amp fuses on each leg. On the other hand if your aftermarket gauge is an ammeter it's most likly the full flow type (junk). If the aftermarket gauge is a volt meter you can hookup one wire to switched ig. and the other to ground the voltmeter gives you very usefull information opposed to the ammeter but I would not use the full flow type of ammeter at all.

The brake light originally went from the sw. on the master cyl to the ignition switch I believe grnd.1 terminal and from there to the instrument cluster the brake light gets its positive feed from another wire which feeds the cluster I'm at work right now but I'll see if I can find that info
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Old 04-07-2009, 01:40 PM   #13
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Re: ez wiring harness questions

Here we go the brake light gets it's power from the 20ga pink wire on cavity #3 of the printed circuit board plug it also feeds the fuel gauge and temp light or gauge and is labeled Fuel ga. feed.
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Last edited by fixit-p; 04-07-2009 at 01:43 PM.
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Old 04-07-2009, 02:40 PM   #14
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Re: ez wiring harness questions

awesome. thanks so much for your help. my only other question, i think, is in connecting the stock ammeter. from the gauge harness is the wire that runs to the batt. term. block and the wire that runs to the alt., correct? the inline fuses should be 4 amp fuses? the existing wires were maybe 16 g, wires with fuses inline. should they be a heavier gauge wire? again, thank you so much.
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Old 04-07-2009, 03:54 PM   #15
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Re: ez wiring harness questions

Correct one wire to the batt junction and the other to the alt junction the stock wires are fine if you look at the diagram below I circled the two fuses and drew an arrow pointing to the red wire (12awg Red) connecting the two points that wire is the shunt and the ammeter measures the voltage differential between the two points the fuses are there in case of a short to ground on either wire to protect the ammeter and the printed circuit board otherwise very little current flows through the wires.
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Last edited by fixit-p; 04-07-2009 at 03:57 PM.
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Old 04-07-2009, 09:09 PM   #16
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Re: ez wiring harness questions

now i'm confused by the starter wiring. does it ever end? i have a solenoid power wire that will get a fusible link and a purple ign. sw. start wire. i swear i only had the purple ign wire on there before. do both the sol. power and ign start go to the same terminal on starter solenoid? why is this different from what i had before?

the dome light has a white and an orange. the white is the power and the orange goes to the headlight switch dome return and the door switches. is that right?

after this it should all be done really. i hope.
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Old 04-07-2009, 10:02 PM   #17
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Re: ez wiring harness questions

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Originally Posted by rage777 View Post
now i'm confused by the starter wiring. does it ever end? i have a solenoid power wire that will get a fusible link and a purple ign. sw. start wire. i swear i only had the purple ign wire on there before. do both the sol. power and ign start go to the same terminal on starter solenoid? why is this different from what i had before?
I would run just the purple start wire to the sol. but the fusible linked power wire is probably better suited at either the batt junction or the alt junction depending on what it's for if it's the main power wire for the cab It would be best at the alt junction but I'm not to sure if the fusible link wire would be a good idea there.

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the dome light has a white and an orange. the white is the power and the orange goes to the headlight switch dome return and the door switches. is that right?

after this it should all be done really. i hope.

The white is the ground and goes to the door sw and light sw. The orange comes from the fuse block suppliing power.

At least you are only confused one ciruit at a time
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Old 04-07-2009, 11:01 PM   #18
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Re: ez wiring harness questions

the solenoid power wire is the biggest gauge in the bunch so it's probably the main cab power. where should i use the fusible link?

i only have 1 wire coming from the harness for the dome. how is it going to get power? if the white is the ground.

if i did it over again i'd have gotten a different brand harness. i had no idea it would be this frustrating.
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Old 04-08-2009, 12:32 AM   #19
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Re: ez wiring harness questions

On the original system the main cab feed was terminated at the alt junction which was a spliced and soldered connection near the left side marker also in that splice was the alt batt wire, voltage sense wire, ammeter wire #1 and the battery charge wire which ran across the radiator to the battery junction along with ammeter wire # 2 and from there was the fusible link and some short 12 ga wire to the batt pos term.

On the dome lights the original system had the orange wire feed the dome lights as well as the light sw. I'm not familiar with the ez system if you could post the diagram that came with it could help.

Last edited by fixit-p; 04-08-2009 at 12:32 AM.
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Old 04-08-2009, 02:14 AM   #20
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Re: ez wiring harness questions

here are the diagrams. for what they're worth.
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Old 04-08-2009, 11:51 AM   #21
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Re: ez wiring harness questions

Wow and you say their tech support is poor. Ok on the dome light look at your headlight diagram the dome return is the ground wire for the circuit and is used for swithing on and off. For power to the dome lights you could tap into (headlight power = red/black) thats the same circuit as originally wired by GM. Fusible link I would not run it to the starter instead run it as I stated before but check out this site first there is loads of usefull info there and you would better understand the charging systems pros and cons, the tech articles are all very good reading.
http://www.madelectrical.com/electri...1.shtml:metal:
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Old 04-08-2009, 12:27 PM   #22
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Re: ez wiring harness questions

I am doing th esame install on a 62 and I have the wire with the fusable link going to the outermost post on the solenoid. and the purple wire going to the inner post, I am not getting any power from the starter at all. Im going to try wiring directly to the battery instead of the alt. since I am using the fuseable link
also as you can see in the diagram you are not running a wire from the alt. to the battery but instead running the red alt pwr. wire provided in the harness so wiring the main feed with the fuseable link to the alt. would be pointless
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Old 04-08-2009, 12:50 PM   #23
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Re: ez wiring harness questions

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Originally Posted by michael bustamante View Post
I am doing th esame install on a 62 and I have the wire with the fusable link going to the outermost post on the solenoid. and the purple wire going to the inner post, I am not getting any power from the starter at all. Im going to try wiring directly to the battery instead of the alt. since I am using the fuseable link
also as you can see in the diagram you are not running a wire from the alt. to the battery but instead running the red alt pwr. wire provided in the harness so wiring the main feed with the fuseable link to the alt. would be pointless
Ok so what EZ is doing is using that wire to the solenoid as the charge wire it would have to be connected to the main post on the starter the outer terminal only gets power when the starter is engaged (used on point systems to bypass resitor wire while cranking) and the main post is connected directly to the battery. Personally I'm not a big fan of putting the charge wire down at the starter the fusible link has a built in resistance to bottle neck the current and exposing it to the extra heat from the exhaust would increase the wires resistence. Since it is the charge wire and not the cab power supply as I orig thought I would run it to the batt similar to the orig oem wiring. mho
http://www.madelectrical.com/electri...evymain1.shtml
http://www.madelectrical.com/electri...evymain1.shtml
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Old 04-08-2009, 12:51 PM   #24
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Re: ez wiring harness questions

Quote:
Originally Posted by fixit-p View Post
Wow and you say their tech support is poor. Ok on the dome light look at your headlight diagram the dome return is the ground wire for the circuit and is used for swithing on and off. For power to the dome lights you could tap into (headlight power = red/black) thats the same circuit as originally wired by GM. Fusible link I would not run it to the starter instead run it as I stated before but check out this site first there is loads of usefull info there and you would better understand the charging systems pros and cons, the tech articles are all very good reading.
http://www.madelectrical.com/electri...1.shtml:metal:

now you see why it's a little confusing. at least for someone who doesn't know this stuff all that well. i have had to look at the painless instructions for a little more insight. i'm getting more lost on this now. argh!

you can see thay have a jumper from the headlight power to what i think is what used to be the power for the dome. i can always troubleshoot the dome later. i really just want to get this thing running without exploding. or rewiring their harness to work right. how should i do this? considering that the alt. power is coming from the fuse box. should i run the sol. power to the battery?

sorry just saw you posted while i was. i'll run it to the battery then. does this wiring setup seem weird to you? sure i guess it will work, but it's so different from the orig. setup.
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Last edited by rage777; 04-08-2009 at 12:54 PM.
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Old 04-08-2009, 01:10 PM   #25
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Re: ez wiring harness questions

I dont know why they would run the main power feed wire from the starter either, like I said I got no power at all. I`ll be working on it more this weekend and Ill draw my own diagram of how I wired the headlight switch for you if you can wait that long
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