Ow do I charge the centry 850 Battery Car Charger I have had for years?

Your Car or Truck has more than one battery?

'year make model' in all vehicle questions, first 3 words.

'make model (what it is)' in all others.

Then put it in the right category from a selection of around 10,000. Then we can help.

If the battery is down, use a battery charger and get charged up. Check battery connections. If you can get it running, check your charging system, and applicable trouble codes.
If hood release is electric, sometimes you use battery charger at starter motor bat terminal, to charge the battery? If you can get at the starter motor?
I don't know model year?

Find where the cables of the car connect to the battery, connect the red clamp of the charger to the red, battery post with the + near it. The black lead to the other post, with the - near it. If you want to slow charge, set charger to lowest amp charge for 12 volt. Hope this helps.

Most likely, Yes.
If you plan to leave your car or not to use it for a month, always remove the negative terminal of the battery. It also depends on the age of the battery, If you have an old battery then it should be 2 or 3 weeks instead of 1 month.

Its depend on the electrical in youf car brand new car 5 to 6 years after 3 year your lucky if you reach 4

#1. Check the secondary cable which runs to your starter.
#2. Check Starter Relay (unplug, and shake it - sometimes to can hear broken stuff inside of them)
#3. Make sure your cables are tight, and your battery has a good charge. (was it trickle charged ? jumping and then turning the car off will not be enough charge for the battery ; you must charge to 100%)
#4. Check all grounds.

1: drive car.
2: connect charger plus to plus and charge it.
3: connect jumper cables to donor car battery , start donor and it charges yours.
4: take it it out, and take it to any shop and say charge it.

google this and get 1trillion hits.
or utube it. same.
or read this book
http://www.amazon.com/Auto-Repair-Dummies-Deanna-Sclar/dp/076459902X

check your alternator it charges your battery if its no good will drain your battery. tip start car and disconnect pos cable on battery with car on if it turns off ur alternator is no good tip

How many amps does this charger put out????
A small trickle charger will take forever to fully recharge a dead battery, you'll need to have a battery charger that can put out enough amps to properly charge a dead battery.To clarify, the chargers sold at Sears, the large square types on wheels are the best for charging dead batteries and they also have an amp meter telling you how much the battery is accepting. After you charge your battery, you should be around 12.5 volts to 12.7 volts. DO NOT OVER CHARGE!!!

it is probably just an old battery problem,if there was a problem with the alternator it would have showed up while you were driving it saying not charging,