1999 Pontiac Bonneville

There is a splice pack that contains numerous ground wires that is located under the drivers side carpet, up close to kick panel, If your losing both windows and pump operation check this for corroded ground wires, I have repaired several Lesabres for the same problem, and the bonnes have the same splice pack.

This is a pic of the splice pack, it is labeled SP340 on the [pic, pull the carpet up on the drivers side and you will see it, there will be a bunch of black wires running into long plastic block, If I suspect right there will be a bunch of green corrosion all over the splice pack, clean and repair as needed.

Thank you man!

No problem, let me know how you do.

Well. This wasn’t it.
The wires were all OK dry and clean. What else can it be? Please also note that while there is no power to the fuel pump and windows the rear defrosts little light on the little button goes on and the electric lucking doesn’t work. However � this car lucks the door while in drive and opens them while in park � pressing the break and moving from D to P and vice versa will open and close the doors. Not manually (pressing the switch) but automatically... Is there a relay that gets hot or something? Hope it is not the computer.

I was sure that would be the problem, while the car is running did you wiggle and move the splice pack around to see if would stall or make the problems appear? I believe this is a ground problem, check the main ground for that splice pack, it is located behind the drivers side kick panel, let me know, we will work through this.

Power locks, windows, fuel pump all share a ground from that splice pack, that is why I gotta believe this is going to boil down to a ground issue.

I did move and pulled it around while the car was running. I appreciate the dedicated help! I will work on it again tomorrow.
Thanks!

Nothing doing. Opened the whole side carpet pulled and shook the whole harness and than even wire by wire and the engine did not stop, it did stop 5 minutes later but restarted again with no issue. I repeated the above and didn’t encountered any problem.
The “side symptoms” changes. The little light on the rear defrost button used to stay on (when the ignition key in power position) as long as it took to get her “back to life” and when the light went off � I knew engine will start. Now the light goes off after two second (with a “click” of a relay at the background) but the engine will not start. I know when the engine will start again because I keep trying the windows, and when the window works � she will start.
Also: This stall problem have no effect by weather of bumps.

Did you check the ground under the driver side kick panel, near the parking brake, take that plastic cover off, there will be a ground bolted to the body of the car, also you need to open that long black box that contains all the grounds and inspect each little black wire, im sorry if I sound like a broken record, but I gotta believe the [problem is there, every compontent that is acting up, even rear defrost, get there ground from that splice pack, they do not share a common power, so that eliminates a power issue, but the thing that they have in common is that ground, This is a known problem, it is all over the tech nets, and I have personally seen this problem on countless Lesabres which is the same body code.

I did not totally open the one near the parking brake only the SP340. Your diagnostic more than make sense. Will go back there... Thanks again for the follow up.

No problem, let me know.

OK � found the problem!
The wires inside the side kick panel, near the parking brake where in perfect shape so I went back to the SP340 harness and bent the plate with the wires at one point she stalled. All still looked good but after more play it became apparent that the wide wire on the bottom of the image attached is the ground that goes to the screw that attach to the body. All the other wires are connected to him through the wide metal plate but although to the naked eye it looks as it plugged in well � touching it causes it to lose connectivity to the plate leaving the rest of the wires without a grounding... Why did they made this plate and isn’t it better if I just hook-up solder all wires to this wide one?
Thanks! You were right!
Arye

Also, now that I think of it � as you can see the plastic cover outside the wide ground wire is melted a bit (on both sides) I did not feel it being hot but did smell hot wire at one point...

ALL RIGHT, Im glad you found it, those grounds will get hot if they are not getting a good gound, because power is backfeeding through the grounds because of that bad connection and getting hot, Get them all cleaned up and resoldered and you will be good to go.

Thanks!
Bless you!

Your welcome, and thank you for using 2carpros.

I am having the same problem with my 1999 Bonneville. The wires in this harness look okay and when I wiggle them one one nothing happens. Any other ideas?

I am not sure, can you direct me where the main pack is? I will try feeling them after I drive it again. Thanks so much for your help!