Author Topic: 81-87 headlight relay mod  (Read 7148 times)

Offline winky

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81-87 headlight relay mod
« on: July 09, 2016, 11:50:52 pm »
Im currently working on my "Modified" wiring harness in my truck and finally think ive finally found a decent program to draw up the schematics in. Please keep in mind usually i have a piece of paper and pen when i do these for my truck and normally only half of it makes it to paper and the other half stays in my head so im sure some things aren't correct but that's the main reason im posting this, i would like some feed back. i figure with all the wiring modifications ill be doing it would be a good idea to go ahead and write diagrams while i do the in case of future issues.

Any ways i figured the head light relay mod would be a short and simple schematic to do a test run on. looking forward to your replies.


Offline hatzie

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Re: 81-87 headlight relay mod
« Reply #1 on: July 10, 2016, 02:28:21 am »
Not only does it give you a reference in case of future issues it also gives you a roadmap for building the harness.
You want to note whether it's the wire or terminal side of any connectors you are re-pinning.

I usually call out wire jacket type and gauge as a prefix to the wire color...  so BRN - 9 would become SXL 16 - BRN - 9

I call out part numbers and terminal position numbers for any new sockets.  Common Open Terminal Mini ISO relay sockets would be Bosch 335-485-008 with 2 x 2989877 & 2 x 2965687 12ga & 14-16ga Packard 56 female terminals.  If you want fully sealed ISO relays they are  Metripack 630 sockets with Hella 007794307 relays.

The H4 headlamp HB2 female plugs use Female Packard 59 terminals.  You can extract the terminals and wire from most H4-HB2 pigtail repair plugs or even the original plugs and install your larger gauge terminated wires.  I would just call out the 6294603 Packard 59 12ga terminals as 6294603 Packard 59F.

« Last Edit: July 10, 2016, 02:31:53 am by hatzie »
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Offline zieg85

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Re: 81-87 headlight relay mod
« Reply #2 on: July 10, 2016, 06:56:47 am »
Carl 
1985 C20 Scottsdale 7.4L 4 speed 3.21
1986 C10 under construction
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Offline winky

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Re: 81-87 headlight relay mod
« Reply #3 on: July 10, 2016, 07:36:30 am »
Not only does it give you a reference in case of future issues it also gives you a roadmap for building the harness.
You want to note whether it's the wire or terminal side of any connectors you are re-pinning.

I usually call out wire jacket type and gauge as a prefix to the wire color...  so BRN - 9 would become SXL 16 - BRN - 9

I call out part numbers and terminal position numbers for any new sockets.  Common Open Terminal Mini ISO relay sockets would be Bosch 335-485-008 with 2 x 2989877 & 2 x 2965687 12ga & 14-16ga Packard 56 female terminals.  If you want fully sealed ISO relays they are  Metripack 630 sockets with Hella 007794307 relays.

The H4 headlamp HB2 female plugs use Female Packard 59 terminals.  You can extract the terminals and wire from most H4-HB2 pigtail repair plugs or even the original plugs and install your larger gauge terminated wires.  I would just call out the 6294603 Packard 59 12ga terminals as 6294603 Packard 59F.



Thanks for the info! As far as wire or terminal side what exactly do you mean? If i decide to change some stuff on the fuse block make sure i id that the stuff i changed was on the fuse block side?

http://www.ebay.com/itm/291011881628?_trksid=p2055119.m1438.l2649&ssPageName=STRK%3AMEBIDX%3AIT

Is what I was going to do when I finish my build

Ive seen them, i just haven't had very good luck with wiring products on ebay. I know its all about the seller but id rather wire it up myself and hope for a clean neat harness. i had originally intended on installing hid headlights but my truck sits too high and im sure it would blind everyone.

Online VileZambonie

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Re: 81-87 headlight relay mod
« Reply #4 on: July 10, 2016, 07:58:43 am »
81-87 also has the 4 headlamp system so you should clearly state which system it is for. What program did you use? I know when I do these I mount them closer to the headlights to reduce the cabling and draw right from a battery bus bar rather than the junction block. Keeps things neater and easier to hide. As far as the harnesses on eBay, I've bought a few and modified them. It was cheaper than buying the individual pigtails and ceramic sockets. The terminals that come on them however are cheap and I would not ground directly to the radiator support  without a direct connection back to B-
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Offline winky

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Re: 81-87 headlight relay mod
« Reply #5 on: July 10, 2016, 08:25:26 am »
Thanks for the input, i meant to state in the diagram that it was for a single headlamps. The last few times ive done this mod ive mounted the replays below passenger side headlights for the reason you stated. Next time i draw one ill put a label with the areas i intend for components to go. I used the tinycad program to draw this, its pretty neat. The main draw back is i believe  it was created to design circuit boards so you have to design most of your own components.

Offline hatzie

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Re: 81-87 headlight relay mod
« Reply #6 on: July 11, 2016, 12:07:25 pm »
Wire side is oriented so you're looking at the side of the connector the wires are inserted into.
Terminal side is the end that plugs into the mating half facing you.

One is the mirror of the other.


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SVC & wiring mans --> Here http://tinyurl.com/7387BRD-SVCMAN or My Bucket @ http://tinyurl.com/SQ-SVCMAN
Parts & Illustr Books -->http://tinyurl.com/SqParts
GMSTG Textbooks-->http://tinyurl.com/STG-TEXTBK
Radio Manuals-->http://tinyurl.com/DELCORADSVC

Offline winky

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Re: 81-87 headlight relay mod
« Reply #7 on: July 11, 2016, 08:46:42 pm »
Wire side is oriented so you're looking at the side of the connector the wires are inserted into.
Terminal side is the end that plugs into the mating half facing you.

One is the mirror of the other.


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Duhh.... that flew over my head lol. I was having one of my moments the other day. sorry