The point of jumping the grounds is to over ride the possibility of an unseen issue with grounds. Just because a ground is hooked up and looks good does not mean it is working without resistance.

You also want to check under dash grounds.

Keep in mind that when I was calling GM for tech support for electrical issues this was back in the 80's and just about every car was untouched by a mechanic and less than 24 months old. They where also much less complicated then a modern car.

The key here is it sounds like you have power going to the alternator when it should not be. I am just guessing here, but if that power is clean, by clean I mean either battery voltage +/- .2 volts or a ref signal 5 volt, you have a wire wrong or crossed. If it is an odd ball voltage like 11.4 volts (with the battery at 13 volts) then it could be back feeding. (aka possible grounding issue)

 

well im finishing up the big 3 upgrade with 0 gauge wire, ive done engine to chassis, batt neg to chassis, and pos batt to pos alt. got home depot 0 gauge thwn wire and took some copper tubing and made my own ring terminals and heat shrink tubing on the ends with 1/2 in split length tubing as well. wish i had ordered the awg rated because that stuff is HARD to bend, like there is NO flex.. its even stranded and not solid copper inside and wow i need pliers to bend it. if it is a grounding issue, it wont be for long. im just putting the finishing touches on it then ill be back to see if it makes any difference. ive also cleaned up the ground sites, stripping it down to bare metal on the points on the chassis. i only augmented the wiring instead of replacing it.. so ive still got the factory stuff there, but also added the 0 gauge wires

 

well i finished it. it did not fix the main alternator noise problem, however.. maybe its like placebo effect or just wishful thinking, but it definitely seems to ride better.

it seems to have cured a couple other minor problems ive been having. one, the shift between 1 and 2 has always(since Ive had the car) been a "hard" shift so to speak. none of the other shifts are like that. well in the 30 minutes ive driven it since doing the big 3 upgrade, ALL shifts feel much smoother. in fact the car seems very responsive now throttle wise(i also did a throttle body p&p recently so may have something to do with that). the headlights look much stronger as well.

when i pulled into a gas station to fill up, the gauges fuse blew again so instead of filling up, i just went straight home. im betting theres got to be something wrong with the cluster for it to blow 5 fuses this week. i know i mentioned i havent had this problem before recently, but it just makes sense that with me toying with every bit of wiring in the car that this issue is now surfacing.

im going to pull the cluster and recheck my work back there with the repinning

 

guys. i feel the need to update. i let this problem sit for many months. i just spent a few hours again with it today and discovered the problem.

SPEEDOMETER. my speedo was causing a little less than 1 V on the alternator excitor wire with car off key off. I pulled it and the voltage went away. now im going to test and see if the fault lies with the speedo itself or if its these red LEDs I put in it. man i feel like such an idiot.

 

Good, you found another path and have to pursue it to the end.
Good for you, sometimes we need a break to recharge and then pounce upon it again.

I would be willing to change red LEDS back to OE bulbs and see if problem goes away.

 

hey everett. so i swapped the bulbs out to the stock bulbs. problem still there. im thinking it probably has something to do with my repinning job.

so i have the 98 service manual and the 2000 service manual, and looked at both gauge cluster pinouts.

i have a suspicion about where the problem is but i wanted to ask you what your thoughts might be on this.

2 areas of my repinning i have question about.

the first: on the 99 cluster pinout, pin A10 is Orange wire "Battery +" and my comparable 98 wiring would be pin A13 Power Feed Power Accy Fuse 7. Fuse 7 on my 98 is the Power Accy Fuse. I have the 98's A13 wire pinned to A10. My question is, would the original difference in these two wires (one being an Accessory power and one being straight battery power) cause the kind of issue Im having?

Also, on the 98 cluster connector, I have TWO pink wires, Pin A1(Pnk, power feed fuse 9 "gauges" fuse) and Pin A5(Pnk, Power feed fuse 9 "gauges" fuse). The 99 cluster connector moved the Pink wire to A3(calling it Ignition 1 Voltage). Currently, I have Pin A1 in the A3 slot and A5 sitting in a loom of unused wires. Should I merge the two Pink wires and have them both run through the slot the 99 uses for the pink wire?

I have gone over and over and over this cluster repinning. My only other possibilities are a few wires that I left in the connector in the original 98 wiring positions just because those little pins are a pain to get out, but on the 99 side were just unused slots. Could those remaining wires play a role? Should I remove them?

Thank you for you help and being patient with my dumb ***. You guys are so right about people coming here only wanting to hear what they want to hear and I have been guilty of that. If i had just listened to you guys this problem wouldve been solved much sooner.

 

well i think i just fixed it. i combined the two pink wires, and pulled the rest of the wires unnecessary to the 99-02 cluster and im not getting any voltage on the alternator excitor any more. woohoo!

 

You're welcome,
Good, and you would want to wire the body to cluster since it is easier to repin the bidy connector than changing the cluster plug.

You might leave a note on connector of the re-pinning as later in life, you won't remember - over 40 thing.

 

I actually have all the wires labelled the way the were originally in the cluster connector and also to where i put them for the repinning, as well as what their function is. I also have all the wires on the passenger side kick panel labelled as to the function/connector/pin/color and their new function so any potential future owner will thank me lol or i will thank myself. Im going to be 30 in October and all the pot smoking/drug doing(and I did it big lol, still technically paying for those silly days) I did in my earlier 20s has already caught up with me and I cant remember anything as is. Thats why Im very **** about this electrical stuff, because one Im not good at it and two I cant remember anything lol.

 

Where did the "99" stuff come from later in your post?
For what it's worth, the 99 service manual is now available online also.