2000 C5 auto coupe. Car has 23,xxx miles.

I bought a brand new AGM battery for the car when I bought it from the previous owner in late 2016. When I bought the car in 2016, it had like 17,000 miles on it? Today it has ~23k miles. I just drive it about 1,000-1,500 miles annually.

I always had the car connected to a trickle charger (always!) until May 2020. I moved in May 2020 and can't get it in the garage (long story). So since May, it sits outside, under a car cover, in the driveway. It has been connected to a trickle charger 0% of the time since May.

I've only driven it 6-8 times totaling ~1,000 miles in 2020.

​​​​​​When I last started it (10 days ago), car cranked for 2-3 seconds, said "low volts" on DIC, then started. Ran fine. I drove it around town for 2 hours.

It sat for the last 10 days. Went to start it tonight. Both "Low Volts" and "Service Column Lock" appeared. Tried to start it. It cranked, but won't start. When key is in "on position", it shows ~9 volts on voltmeter in dash.

I just hooked it up to Battery Tender. It says it is charging on the Tender light. Is that my best bet? Should that work? How long until it has enough juice from Tender to start?

Will I need to jump it? If so, I heard jumping these cars is bad? Is there truth to that?

Philly area. 30*F outside. Lights work, power locks work, but won't start. Cranks, but no start.

Not sure what to do. Thanks for any help.

 

Your best bet is to remove the battery and have it charged and load tested

 

Not to sound like an idiot...but no idea how to disconnect the battery.

Will the trickle charger give it enough power to run or highly unlikely?

If I have it jumped by AAA, is that bad for it? These C5s are so finicky with electronics.

 

If charging the battery for two days doesn't bring it back, buy a new battery, There's nothing wrong with using jumper cables to start the car.

 

The first thing I’d do is get the trickle charger on it...my charger has a green light that shows it’s fully charged...a fully charged battery is 12.66 volts...can you at least get it charged to this voltage ??...maybe a parasitic drain test could be done...if you don’t know how to do this see how much the battery voltage drops after an hour or two...we usually see how many milliamps the car draws when it’s “asleep”...around 20-30 milliamps is good...getting the battery load tested would be advisable... I’d also check the charging voltage at the battery terminals while the engine is running.

 

Even if the battery is good, a trickle charger may not get the battery over the goal line. If you can get a regular charger on it, that would be better. Whatever you do, don't let the battery go dead. A dead battery can freeze and the case can crack and leak acid in places you don't want acid.

 

Check and clean battery connections and load test as previously stated. If you don't have a load tester bring the battery to Advance Auto, Auto Zone or somewhere they will test it for free (and be happy to sell you a replacement)

 

Thank you all!

Thank you very much Smoken1 for guiding me through this!!

I stopped by Advance Auto and grabbed a 78 series Diehard AGM Platinum battery (battery in the car was a 4 year old Diehard Gold AGM).

Bought some tools that Smoken1 told me to get. Watched a quick YT video. Never changed a battery before.

20 or so minutes later, started it up. Roared! Service column Lock and the low voltage messages were gone. Car is purring through the Corsa Xtreme exhaust. Running better than ever.

Dam are these cars battery hogs. Is it the computer running that draws power when it's shut down?

Either way, perfect again. Thanks!

 

Yes, the constant 20-30 ma load will drain a battery in a few weeks so if you store it for a long time without a charger keeping it charged then disconnect the battery from the car.

 

Glad to hear your C5 is up and running again. Merry Christmas.

 

Good for you man.!.... Now you know more than the ordinary guy or tow truck driver.... C5 cars eat batteries and charging and trickle charging won't do squat for a "used-up" power supply... Always go there first (the battery) with a non-starting Corvette C5 or you'll be chasing illusions and replacing starter motors and other things!.. Ask me how I know!

 

A new battery can make things right again - glad you got it started.

 

You'll still need a battery tender if the car is going to sit for any length of time with the battery installed. Your wording of trickle charger is best to be a battery tender or C-tek. Those both do the job of keeping it fully charged all the time..Both my C-5 and GTO have tenders on them right now and will be until April. I don't start them or anything for around 5-6 months and have never had a problem.

 

If the car is sitting for a while without driving and you don't want to leave it on a charger for some reason, just remove the negative cable from the battery it will likely be ok this way for a few months.

 

Get rid of trickle charger get a battery tender, maintainer