Page 1 of 1

battery issue

Posted: Sat Aug 30, 2014 4:44 am
by sjeburgpa
i have a 2001 gl1800 battery is losing charge quickly with everything off went from 12.4 v to 9.4 v overnight brand new battery 2nd actually help where to start looking

Re: battery issue

Posted: Sat Aug 30, 2014 7:58 am
by mikelens
Process of Elimination.
#1. Disconnect battery completely and see if it holds voltage. Holds=Battery Good
#2. Connect Positive battery terminal. Leave negative cable disconnected. Connect a volt meter, set to read amps, between the negative battery post and the negative cable. This will show you the amount of draw on the battery. You should see minimal draw: 1/4- 1/2 amp. Higher draw indicates a short to ground.
#3. Pull fuses one at a time till the draw indicated on the meter drops. That would be the circuit with the short. A service manual will show you what is on that circuit. You'll have to check switches & wires on that circuit.

Re: battery issue

Posted: Sat Aug 30, 2014 8:24 am
by Fatwing Chris
mikelens wrote:Process of Elimination.
#1. Disconnect battery completely and see if it holds voltage. Holds=Battery Good
#2. Connect Positive battery terminal. Leave negative cable disconnected. Connect a volt meter, set to read amps, between the negative battery post and the negative cable. This will show you the amount of draw on the battery. You should see minimal draw: 1/4- 1/2 amp. Higher draw indicates a short to ground.
#3. Pull fuses one at a time till the draw indicated on the meter drops. That would be the circuit with the short. A service manual will show you what is on that circuit. You'll have to check switches & wires on that circuit.
You are right on with the process,but your spec is too high.
1/4-1/2 A= .250-.500 mA which are both way too high.Normal parasitic draw is approx. .005 mA which is 5 one thousands of an Amp.A totally loaded up with options car has a draw of less than .050 mA.

Re: battery issue

Posted: Sat Aug 30, 2014 3:08 pm
by MikeB
Check to make sure you didn't leave something plugged into a power port or a trunk light turned on.