Confusing Battery Issue

[didymas]

I bought a 2003 LS in October and have been using these forums to lookup advice since then but now I have a question that I can't figure out...

Background: My battery died this January when it was -40 out. I replaced it with a new one and everything was fine until about a month ago.

A month or so ago I went out to lunch, car was fine driving to lunch, when I came out it didn't start, didn't turn over or anything, and no lights were on. Tried to start it a few times and nothing happened. I thought to myself "Did i leave the dome lights on?" and pushed the button to see if I had. When I pushed the dome light button everything turned on. I then tried to start the car and it started right up. I thought "That's weird." and then kind of forgot about it.

Last Wednesday it didn't start again. Remembering the previous incident I pushed the dome light, nothing. I ask a friend to come give me a jump. (Then have to break into my trunk through the seats because my trunk key doesn't work) He pulls behind my car. I go to connect the positive clamp to my car (while nothing else is connected to the jumper cables) and as soon as I touch the clamp to the terminal all the lights on the car turn on. I try and the car starts right up without any jumper cables attached.

The same think happened again last night. everything dead. touch jumper cable to terminal everything works. I didn't even bother calling someone to come jump me this time.

Terminals on the batter don't have any corrosion and everything is connected tightly.

So, what is wrong with my car and are my jumper cables filled with magic?

 

[LS4me]

I bought a 2003 LS in October and have been using these forums to lookup advice since then but now I have a question that I can't figure out...

Background: My battery died this January when it was -40 out. I replaced it with a new one and everything was fine until about a month ago.

A month or so ago I went out to lunch, car was fine driving to lunch, when I came out it didn't start, didn't turn over or anything, and no lights were on. Tried to start it a few times and nothing happened. I thought to myself "Did i leave the dome lights on?" and pushed the button to see if I had. When I pushed the dome light button everything turned on. I then tried to start the car and it started right up. I thought "That's weird." and then kind of forgot about it.

Last Wednesday it didn't start again. Remembering the previous incident I pushed the dome light, nothing. I ask a friend to come give me a jump. (Then have to break into my trunk through the seats because my trunk key doesn't work) He pulls behind my car. I go to connect the positive clamp to my car (while nothing else is connected to the jumper cables) and as soon as I touch the clamp to the terminal all the lights on the car turn on. I try and the car starts right up without any jumper cables attached.

The same think happened again last night. everything dead. touch jumper cable to terminal everything works. I didn't even bother calling someone to come jump me this time.

Terminals on the batter don't have any corrosion and everything is connected tightly.

So, what is wrong with my car and are my jumper cables filled with magic?

First off...... Why doesn't the trunk key work? Wrong key? Valet key?

What brand vented battery? Who installed it? The jumper cables aren't "magic", but the battery may have an internal failure; like the terminal may have broken loose from the plate.

 

[joegr]

Those symptoms are common for a marginal connection. This could be at the battery clamps, within the battery cable, or internal to the battery. (There are other places too, but since touching the terminal had an affect, I think it will be one of those three.)

BTW, the LS has a battery saver. If you leave the trunk open, or a door open, or the glove box open, or a map light on, it doesn't matter. The batter saver circuit will cut the SSP relays after 20 or 30 minutes anyway.

 

[LSV8FAN]

I disconnected the battery when replacing the air intake and left the trunk open. The rear of the car was sticking out of the garage and it started to rain, so I closed the trunk and, like "didymas" above noted, the trunk would not open with the key. Looks like there is no mechanical linkage between the key and the lock and the key activates a motor/solenoid that opens up the trunk. The "related flaw" in the design is that the rear seat back release cables are only accessible from the trunk. I also "broke through" between the seat backs with a wire with a hook and used to pull the emergency release cable to open up the trunk. Aside from looking for the seat back latch with a screwdriver from the top of the seat back, is there a "save electrical" way to do it? Like plugging in a 12V source into the cigarette lighter.

 

[joegr]

... Looks like there is no mechanical linkage between the key and the lock and the key activates a motor/solenoid that opens up the trunk. ...

That comes up every so often, and it is completely, 100% false. The trunk opens from the key via a mechanical cable and requires no electrical power whatsoever to do so.
Maybe your trunk lock cylinder has failed, or maybe you only have a valet key. Either way, having the battery connected or not has no bearing at all on the key opening the trunk. I use my key in the trunk every now and then just to make sure it is working. Same for using the key in the door.