C4 Dead Battery

I have a1988 convertible with the 4 + 3 tranny. If I didn't drive it for about a week, the battery was dead. I thought it might be a defective battery so I replaced it and had my mechanic check it out. He reported that the charging system is OK and that there is only a

17ma draw when parked, which is acceptable. After a week without driving it, it is dead again. Any ideas???
Reply to
aviation
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Invest in a battery tender. I had the same problem with my 86 coupe and after I started using the battery tender always charged up.

Reply to
Bob Gee

'94 lamps might be different from '89 but I had one of the under hood lamps that didn't always turn off. Disconnected the connector, no problems since.

Reply to
PJ

=================== I second the Battery Tendar ...but I had the same problem...with the same cause in both my 79 and in my 95 with the under hood light not always shutting off... disconnected both and no more dead batteries... PS...I still use the Battery Tenders on all my cars when I know I will not be driving them for a week or more...and of course over the winter. Before using the battery tenders I was replacing at least 2 batteries every spring...after the cars were stored during the winter...

Bob G.

64 72 & 98 Convertibles 76 & 79 Coupes
Reply to
Bob G.

Yeah, here's another thought. I had the C4 laid up since the first of the month and fired it up yesterday. Was ready to pull out the charger but checked the batt voltage before I turned the key. (11.3 volts -- out of a four year old battery). I then thought back to this thread.

Several years ago, my '89 developed a high resistance short (to ground) in the *ground* wire to the spare tire lamp and this was bleeding the battery down.

This circuit is a bit unusual since the 'hot' side of the spare tire lamp is hot at all times. The ground is provided by the interior light circuit. In the '89 there are enough lamps on this circuit that a partial ground can draw a lot of milliamps but the lamps won't glow. The infamous delay timer also plays in this sandbox so it ain't easy to troubleshoot. You might take a close look at the wiring near the spare tire. Seems strange that this wouldn't have showed up during the mechanic's stray current check -- might be intermittent.

-- PJ

Reply to
PJ

My 1984 battery would die after a week or so..no number of replacement batteries or electrical checks could cure it...I then en changed the ceasefire system to a 1990 TPI system with a new 1990 computer...I never had a dead battery again..even after a couple of months of storage...the only elect item changed was the computer ecm...so I have been told the problem must have been computer related..????

This seems to be a very very common problem with C-4 Cars...and there does not appear to be any single solution to it....it drives everyone nuts..can't even leave your car at the airport and expect it to start after a week...sad situation..but then it is a GM product so what do you expect.

Reply to
Maddog

Many yrs. ago I got tired of chasing electrons on my '75 to find the reason for my dead/weak battery. I added a battery disconnect to the battery and simply disconnect the system while not driving. End of problem. They are a cheap fix when you run out of patience/ideas.

Reply to
W. Moore

wouldn't a "battery disconnect" lose the memory settings in the radio and other componets like trip meter ?

Reply to
'Key

Reply to
RicSeyler

The only memory in the '75 is mine and that doesn't work very well any more. :-)

Reply to
W. Moore

Yes....Mine is doing the same thing....the short is in the dashboard cluster. I put a brand new battery in it this year, and within a week I went out to start it, and nothing....A mechanic told me he tracked it down to the circuit board in the dash....not sure if that is your situation, but it was a common problem...

Fwed

Reply to
fweddybear

well - duhhh! my bad.. I was thinking more of the "C$"

Reply to
'Key

hell, I thought it was only happening to me :-)

Reply to
'Key

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