No power to the rear lights or fuel pump trigger after putting Stuff in trunk. Please see pics

65psiboost

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Joined
Oct 25, 2017
hi guys/girls happy holidays to all!!!

Ok, I apologize if this was already covered but I did do a search and couldn’t really find what I need.

So we did some Christmas shopping in the GN. After we loaded up the trunk with gifts and groceries the car wouldn’t start and I had absolutely no power to the tail lights or fuel pump. After taking everything out I noticed the Circus of weak and frail wires that I guess I accidentally pulled right from the 2 male plugs seen in the pics.
With the help of google I was able to figure out which wire was the fuel pump trigger and after cutting some insulation off and twisting them together I was able to bypass that Corroded connector and got the car started up. My pump is hotowied but this was the trigger wire from the ecu.
Later on today I plan to replace all of that frail trunk harness wire with some better quality wire and loose that double connector. but unfortunately I have no idea what wire goes where because the whole wire pulled out of the connector from the weight of the cargo we put in the trunk. So I could really use a schematic or diagram of what color goes to what color before and after that connector. I don’t think the colors actually match up after the connector. So any help would be greatly appreciated because I had to drive home at night with no rear tail, stoplights, rear turn signals,or reverse lights. As of right now I have no rear lights.

Please see the pics. I had no knowledge of this mess because it was nicely tucked away under some nice aftermarket trunk interior covers.

Thank you and have a blessed day
 

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The connector in the Trunk is C320. As I recall the wires that run from C209, next to the fuse box to C320 in the trunk are solid aluminum for some god only knows reason.
 
The connector in the Trunk is C320. As I recall the wires that run from C209, next to the fuse box to C320 in the trunk are solid aluminum for some god only knows reason.
Yea I know I just found that out today. I’m getting a lot of unwanted resistance because of that while rear tail light harness. But I guess it’s whatever. As long as it’s working again. I even bought new bulbs and cleaned all the contacts with that $10 can of contact cleaner spray lol.
 
Well I did the best I could with replacing all of the corroded wires. Now I have the following problems:
No drivers side brake lights
No drivers side rear turn signal
No drivers side hazard lights
No reverse lights on either side

Everything on the passenger side works great. And the regular taillights on both sides work.

Can anyone provide any suggestions? What wires i should look at?
Thanks
 
Can anyone provide any suggestions? What wires i should look at?
Look at the wiring diagrams, and trace them out. Disconnect the in trunk harness plug, and power check, the wires. Then, unplug the bulbs, check continuity/ ohms in the wire from the plug to the bulb. If power is at the plug, from the front, the connectors in the plug are at least good enuf to carry voltage. Plug back in, and unhook the non working bulbs, check again.
VISUAL inspection is a MUST. Checking w/ an ohm meter beeper, only tells you that as few as 1 strand of wire is still good. Volt drop test time.
Could be, that the plug is fried, and has to be replaced. Cleaning connectors w/ harsh chemicals takes the coating off, and the connection is suspect for further issues. {John Spina, 1949.}:D Green grunge under the pin crimps is fatal!
I'd suggest, rather than trying to get an oem plug, cut the wires, install a Weatherpak plug.
While you are at it, find out why the oem stuff is rotted. Trunk seal leaks? Area at base of rear glass, under the panel, rusted out, area below the plug rusted out? Trunk floor rotted where the gas tank mounts? Rubber seal and harness retainer still in place?

NO house wiring nuts, twisted wires w/ elec tape?:eek:
Solder and shrink wrap ALL repairs. We use the good shrink tube w/ the adhesive in it.....
 
As I recall the wires that run from C209, next to the fuse box to C320 in the trunk are solid aluminum for some god only knows reason.

Years ago (early 90's), before I owned my car, the original owner had some ghetto alarm system in place that would blink the lights and make all kinds of ridiculous annoying sounds, even when the wind blew too hard! Then all the lights were giving me trouble and I had to pull out this birds nest of a wire debacle.

When I discovered the aluminum wire harness, If given the opportunity, I wasn't sure who I would violently beat first! The ghetto idiot who installed the alarm or the "cost engineer" at GM who thought the aluminum wire harness was a good idea.
 
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Thanks for the input.
Everything on the now Working great!!
I wound up de soldering 99% of that aluminum wire that the harness is made from. I am now the proud owner of a full copper wire harness all the way to the fuse box under the dashboard. I ditched that corroded harness plug and replaced it with one from autozone.

To answer the above question. Yes, this car had seen a significant amount of rust that I have been fixing up little by little. See I didn’t wanna ruin the 86 GN that my dad bought a few months before he passed. I wanted to keep that one bone stock and with less then 30k on the clock. But I also wanted a GN that I could mod, daily drive and beat on. So this is my “fun” GN. My dad’s GN was stored for me from 86 till 90 the day I turned 16 my mom gave me the title and keys to it. But I really only drive that one on special occasions.
I still consider that my dad’s car

Well anyway thank you guys for coming through once again for me with all the info I needed to fix this problem.
God Bless y’all
 
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