JakeRobb

So, life has gotten in the way and lately I've needed to drive the Bonneville a lot (need the extra space). Last night I finally had a chance to drive the Camaro. It's been sitting about a week.

So I got in. It chimed when I put the key in (door still open). Close door, turn key. The dash lights up as I turn past ACC, but when I got to ON, the dash lights up like normal for a fraction of a second and then everything goes dark (even stuff like the dome light when the door is open). Back to ACC and everything comes back on.

So, it appears that the whole car is losing power whenever the key is in the ON position.

It's possible that the battery is going bad and just doesn't have enough power to run all of the stuff that comes on when the key is ON, but the battery is less than two years old. I'll check the charge tonight, but I'm assuming this is either a short or a bad connection somewhere. It doesn't seem like a fuse or relay, given that it works for that fraction of a second each time.

I only had about 30 seconds to look at it last night, so all I've done is confirm that the battery terminals are tight. Obviously there are a few more things I need to look at, but if anyone has seen this exact behavior before and already knows what the problem is, I'd love to save myself the time when I get home tonight.

Thanks guys!

Chevyssoccer

I would guess the ignition switch, but its alot easier to check the battery first, and possibly the terminal on the ditribution box for corosion

JakeRobb

Well, ~20 hours later, I went back out to the car. I hit the unlock button on my remote and the power locks made a weak little noise. I think I must not have locked it last night, because the door opened anyway. This time, no dome light. No chime when I put the key in, and nothing at all as far as dashboard, radio, etc. Pushing buttons on the remote doesn't do anything anymore -- that little noise apparently came from the very last milliamp the battery could muster.

So clearly, the problem is that the battery is dead. This leads me to believe with some confidence that the problem yesterday was that the battery was mostly dead. (Insert "The Princess Bride" reference here.)

I've hooked up my charger, and we'll see what happens in the morning.

Anyway, now I have a new concern: generally, the only way to kill a two-year-old battery this thoroughly in a week is to subject it to some kind of constant, nontrivial current draw. If it was a big drain (like a dome light or something) it would have been totally dead in less than 24 hours. The clock and radio preset memory drain takes months to kill a good battery. So, it's something in between. If I just charge the battery, it'll probably just drain it again, so I need to figure it out.

Anyone have any bright ideas about what it could be? I was under the impression that our cars kill accessory power after ~10 minutes with the key out, and won't turn it back on until you put the key in again and turn it to ON or ACC, or open a previously closed door (or the hatch). Is there anything that's not on that circuit that might do it?

The distribution block and all of the major electrical terminals (battery, starter, alternator, and the various grounds) are clean and free of rust and corrosion, as is the rest of the car.

dangalla

if the battery is going dead it will not take long for it to die even if there is not much of a draw, i would have it tested

if it tests okay you can do a parasitic draw test with a test light and pull fuses until it goes out to narrow it down, if it gets to this point i will explain in detail how to do it correctly - but i think you just have a bad battery

JakeRobb

Yeah, I know how to do it. I don't have a test light, and the nearest place that does tests is 20 minutes away, so I'm trying to find shortcuts.

dangalla

do you have a multimeter, or even any kind of automotive bulb that you can solder two leads onto

JakeRobb

I do have a multimeter (guessing you're referring to just looking at the current numbers), and yeah, I guess I could probably build a test light. I don't know why I didn't think of those things.

razor02097

clearly your Camaro is angry you made her sit a week while you drove around another vehicle...


Check for signs of critters... small 4 legged gnawing machines can tear your wires to ribbons in 2 or 3 nights. If the car has sat a week I wouldn't rule it out.

dangalla

yeah to be honest you should take a amp draw reading to be exact, but a test light is usually quicker and easier to do. usually up to half an amp is acceptable. i know you said how to do it but just make sure you set everything up and wait for the accessory delay relay to turn off, and when you disconnect the battery make sure the test leads do not become disconnected or it will reset the relay
usually on a side post battery i disconnect the terminal and find a bolt that will thread into the battery, then use a jumper wire to connect the battery to the harness terminal and hook up the multimeter probes (or test light leads), wait until the relay shuts off and then disconnect the jumper wire and take your reading

if you don't do it everyday its acceptable to not think of these things, i am absolutely sure i do not think of many things with computers or apple that you would think off right away

JakeRobb

So, I feel stupid. Prior to last night, I had spent approximately 90 seconds total with the car, trying to figure out the problem. Last night I actually had some time to spend. On the way home from work, I stopped at the store and bought a test light ($8 ).

First I released the parking brake and rolled the car out of the garage (it's a smallish garage and the lighting isn't very good). Just for fun, I checked to see what sort of symptoms I had after a day on the charger. Lock/unlock worked fine, radio worked, dome light, door chime. So I turn the key. The starter kicks for a tiny fraction of a second and then the whole car dies again. Fine. I left the key in ON and went back under the hood.

To make sure the test light worked, I first put it directly across the battery terminals. Okay, it lights right up. Cool. Then I put it across "AUX BATT POS" post next to the fuse block and the ground on the shock tower a few inches away. No light. Great, I think I found the problem already. To rule out a ground issue, I tried from that ground to battery positive -- lights right up. Then I tried from battery negative to the AUX BATT POS post -- nothing. So clearly I'm not getting power to the fuse block. I trace the heavy red cable that provides power to that, and I find that it simply goes straight to the battery.

So I grab the big terminal that's connected to the side of the battery and I try to move it. It rotates around the battery post easily, and as it moves, I hear a bunch of clicking, I hear the blower motor fire up, and the door chime starts going. Great, sounds like we have power. I grab my 8mm wrench and tighten that battery terminal connection a bit, then go try the key. Car fires right up!

So, I feel stupid because, as I said in post #1, I had already checked that the battery terminals were tight. I didn't put a wrench on them then -- just wiggled by hand. I found no movement and assumed they were tight. I don't know what's up, but the positive terminal sure moved easily last night.

Anyway, the battery and the rest of the car are fine. Since it was working again and I still had some time to kill before my wife got home, I decided that 20-minute drive to AutoZone wasn't so bad, and I went and bought a couple bulbs I needed -- CHMSL and front turn signal -- and then took the long way home. God, I love driving that car!

Side note: the CHMSL installed easily (good thing I have torx drivers -- seriously GM?), but when the old bulb burned out it apparently got hot enough to deform the bulb glass -- it was almost too large to come through the opening -- and to char the plastic socket. Weird. Also, why must changing front turn signal bulbs be such a PITA?

Marc 85Z28

You're symptoms are typical of the classic poor connection on a side post terminal battery. I HATE side post batteries. I have 5 GM vehicles, and have converted all of them to a standard to post. Although I've only had problems with my 2 F-bodies... Maybe it's a vibration thing.

I see this often on all makes and models that use "peanut bulbs" for exterior lighting. 168/194 and 918/921 bulbs.