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Electrical - Possible causes for a flat battery

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Electrical - Possible causes for a flat battery

Postby TechTeamMod » Tue 9th Sep 2008, 06:37pm

  1. Bad battery - easy to fix, change battery
  2. Bad Alternator - check by jump-starting the car and measuring output with multimeter. 13.8V or there abouts. If it's not charging, get a refurbished or new one.
  3. Loose fan belt - check condition and replace/adjust as necessary
  4. Bad Earth - check all earth straps, make sure the connection is clean, add a few new ones...
  5. Drain - alarms, stereos, old worn switches and short circuits all drain batteries
If its not one of these then try looking for other problems...

Check all wiring to the alternator, starter solenoid, headlights, clean up connections, re-insulate those that need it.

If you think you may have a discharge, first look under the car at your battery cable - is it split, are the metal holders touching the inside wiring causing it to short?

Next check your fuses with the ignition off check if there is current and if it should be there.

Watch out for standard Rover stereos as they sometimes go faulty and draw current.

Many thanks to our members for the content of this article.
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