View Single Post
Old 02-04-2002, 09:49 AM
Posts: n/a
Get yourself a digital voltmeter - they are cheap. Check the voltage at the battery - car off - should be 12.56- 12.9V. If it is lower - put an automatic charger on battery until it shuts off. Measure the battery voltage - it should now be 12.56 or higher. Wait for an hour and check it again - if it is significantly lower - you have major voltage drain - suspect the alarm and or wiring of it. If the charger won't shut off automatically at all- you really are pumping a lot of current. Put the voltmeter on the battery and start the car - LEAVE ALL LIGHTS AND HEATER MOTORS OFF - The voltage should be MINIMUM 13.2 V but 13.4-14.2 indicates a good alternator output. If this voltage is not there - while engine is running - check the voltage at the output of the alternator itself - if it is 13.4 -14.2 there but not at the battery - CHECK YOUR WIRING. If it is not at the alternator - you probably need a new alternator.The digital voltmeter is indispensable for troubleshooting this kind of problem. JUST WONDERING GUYS - I have never done it - but if the installers of the alarm system shorted the output of the alternator to ground while the car was running - could they have shorted the diodes in the Alternator? If the diodes in the alternator are shorted - could they not then drain the battery as this fellow is experiencing? Is it possible???
Reply With Quote