Questioncar has been off The road for 5 years waiting for my son to start driving. had been starting...past 3 weeks has been starting fine after new battery...then unable to turn over. Spark plugs, alternator and air filter replaced yesterday. Wont start again - seem more like battery is dying but able to start when jumped.
Any suggestions?
AnswerIf the car jump starts normally, you've pretty much determined the battery is discharged. So the potential problem types are only a few:
1. Defective battery.
2. Alternator not recharging the battery.
3. Excessive parasitic draw (drain on battery while vehicle off).
You'll need a digital multimeter to make the following checks:
-- Jump start the car and check the voltage at the battery terminals. It should be 13.5 to 14 Volts. If it is 12.8V or lower, you have some sort of charging issue. The most common issues are a blown main fuse or a defective alternator.
-- With the key out of the ignition, remove the negative battery terminal from the battery post. Set your meter to the highest Amperage scale and place one lead on the battery negative post and the other on the negative cable terminal end. This value should be less than 50mA, but 100mA is likely low enough that you'd have no issues. It's okay to change scales if necessary to obtain the proper reading, but only do this after you've taken a measurement on the highest scale. This way, you'll have an approximate value for the current and can choose a scale that is low enough to provide good resolution yet high enough to prevent damage to your meter.
