Battery draining

[wanoennogs]

I replaced my car battery last Wed due to my car not starting. Everything has been fine until today. Today I have the same problem as last week. My car won't start. I am wating on a friend to give me a jump start.

What could be draining my battery? Radio and lights are not being left on.

 

[Harry Bloomfield]

What could be draining my battery? Radio and lights are not being left on.

There are lots of possibilities, you start, by measuring the actual level of discharge, then if there is one, pull fuses for circuits out one by one, until the discharge disappears.

All modern cars do have a normal level of discharge, usually between 10 and 40mA, just to maintain alarm, ECU's, and clocks etc.. Most modern cars will flatten their batteries anyway, if the car is left unused for 4 to 6 weeks.

 

[Tricky-Dicky]

Or your alternator not re-charging the battery!

 

[Harry Bloomfield]

Or your alternator not re-charging the battery!

He did say, it went flat, whilst stood, but...

Connect a dc 20v meter across the battery terminals. Engine off, it should show maybe 12.5v -ish. Start the engine, it should show 14.0v/14.5v. Turn everything on, and it should still show close to 14v.