My car battery is totally and completely dead on my G5 2008 Pontiac as the lights were left on overnight. There were zero indications or problems before. I tried to charge using cables and it was totally dead still. HELP!!!! Thanks....

battery dead --charger failure --improper connection with charger --connector port problem

It is a type of security system. Like you said all functions are turned off until you push button because battery is disconnected from system.

You need a new battery, it is triggering the secuirty system lock out

When the car is running check the voltage at the battery. You should see 14 volts. If you see around 12 volts or less the alternator is not charging.

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Check the total wiring connections with battery.Check that there has been overlapped positive and negative wires or not.

You do not indicate which Mercedes you have. On some the battery is located under the hood on the right at the back. On others it is located in the recess panel behind the rear wheel arch in the trunk

yes it is the battery,was it a little cold out this mornin??? cold weather usually exsposes the bad batteries in vehicles,and sometimes there is no warning but your battery is old and should be replaced,hope this helps

Check batteries for dead cells, check brake pads. Have power control unit checked it may be faulty. .

Either an interior light or head lights were left on all night, or there's a dead short in the electrical system, or... the battery completely failed internally such as a weak spot or defect in the plates. At any rate, it all obviously points to the battery. Replace the battery.

have you not left any load on overnight?..like park light or left the door partially open and the dome light would be left on?

have the battery recharge and the next night, make sure that no light would be left on the car.

if it would drain out again, have it recharged again, use it and on the night, make sure no light is left on the car, then remove the positive pole on the battery overnight.

the next morning, put the positive cable back and start the car.

if the car would start, then no problem with the battery, if the car would not start, then return the battery because it is defective.

tnx 4 using fixya,

drcool