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2000 bonneville battery - under back seat?

07-13-2003, 11:50 AM
i was considering purchasing a 2000 bonneville SE, but a friend warned me against it because he claims that the battery is located under the back seat, and that this is very dangerous because in an accident the battery will often leak acid, burning the back seat occupants. This is a major concern, since this is a family car and children will be riding in the back seat. He claims that the battery was located there in the 2000-2001 bonnevilles but was moved for model year 2002. I have not yet looked at one of these cars myself, so i ask: are these claims true about the battery?

07-13-2003, 08:42 PM
Yes the battery is under the seat. GM out it there because of a lack of room under the hood. The battery is in the middle under the seat, I have yet to hear anyone having a problem with it being there.

As for an accident the battery is located between the crumple zone and should be safe. Even if it did leak acid, it would just splash the seat and everyone would be out of the car before the acid could eat thru the seat.

I have 3 kids and have no problem of where the battery is located. It just as easy to get hit with battery acid under the hood as it would under the seat.

Just so you know I work at a Buick, Pontiac, and GMC dealer.

07-14-2003, 09:20 AM
makes sense. the area below the center rear seat is a pretty protected spot. I just wonder how well it would hold up in a rollover crash, but then again, the bonneville is pretty wide and low to the ground.

07-22-2003, 08:40 PM
Kyle, I read that Pontiac moved the battery to under the back seat to better equalize weight distribution. Normally with the battery located in the engine compartment under hood it hangs on the unibody. GM claims that in order to lighten up the front end new Bonnies (2000+), they re-located the battery to under rear seat. It sort of makes sense, I'm not an engineer either. The battery is sealed, and has that ventilation tube configured to let it breath to exterior of car, Im not sure it really represents a great hazard.

07-23-2003, 07:00 PM
Actually the real reason the battery is under the rear seat is simple! The battery is located in the center of the car which means GM saves money by using shorter wiring harnesses. You don't need to go from the front of the car all the way to the trunk with every single wire. Instead of 30 feet of wire you can do this now with 15 feet of wire. Mulitple that by every car built and you have major savings. Do you think GM really cares about an 80 pound battery under the hood of a 2000? pound car?

Its all about the money! I heard this in a GM tech school!!!

10-04-2004, 05:12 PM
i recently purchased a 2001 bonneville, and too found the battery (and the fuses) are located under the back seat.

I for the life of me cannot get the rear seat off. The directions in the owners manual are kinda vague, so I'm looking for a little more detailed description. So if anyone out there has done it. . .how is it done?

I don't have a reason to get under there now, but would like to know I can if I ever have to later.


10-05-2004, 06:18 AM
You really have to pull up hard on the front side of the bench seat to get the clips to release.

10-06-2004, 10:57 AM
Seems like the wiring excuse is weak to me. Most of the controls for the engine, dash, etc are in the front half of the car, plus you need long power cables which are heavy gauge, thus expensive, going to the engine for the alternator/starter. Seems like if anything it would take more wire being in the backseat. There is probably only a dozen or so wires going to the trunk. Whats in the trunk, some tail lights, courtesy lamp, trunk release, etc. I don't buy the wiring explanation, not that its a big deal anyway. I like it under the seat. Better weight disturbution and keeps it out of the damaging heat/cold of the engine area bay. Kudos to GM.


10-11-2004, 10:12 AM
My '02 SSEI actually has two batteries, one under the hood and one under the rear seat. Asked my dealer why there were two and was told because of the large electrical demand from stereo, OnStar, etc etc (my bonnie is "loaded" ). Have had the rear seat out to install wiring for a sub amp and you do really have to pull hard to get it to pop loose. Goes back in pretty easy tho...

04-22-2006, 09:23 AM
I have a 2001 Bonneville with battery under rear seat and think its a great place. I found easiest way to remove seat is to reach under back of rear seat and pull up on seat. The front then comes up easy. To reinstall insert front of seat first into notches making sure seat belts are up on seat properly then push down on rear of seat. Done!

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