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Frank-id · 11-26-2003, 08:55 PM

To check modern vehicle electrical, a digital multimeter is required. A 12 volt lead acid battery, as used in cars and trucks, will indicate 12.6 volts with a DVM. A battery that measures 12.0 volts is 75% discharged. A digital volt meter is a great electrical test tool. Even the very cheapest digital meter will give lots of valuable information. A battery voltage that is low will not "excite" an alternator to begin a charging voltage of about 14.7 volts. The alternator voltage must be higher than battery voltage.

To determine if there are any phantom electrical loads on a battery, connect a horn or any 12 volt lite between the battery negative post and the battery cable. If the lite come on or the horn beeps, there is a load. By unplugging and removing lite bulbs and disconnecting the wires to the alternator, the battery drain may be located. The only acceptable load is the clock, whichs rewinds the clock very quickly. The most common loads are the alternator, heater motor, trunk and glove box interior lites...... Frank

11-26-2003, 08:55 PM	#15
Frank-id Registered User Join Date: Sep 2003 Location: Twin Falls, Idaho Posts: 73	Batteries and electrical To check modern vehicle electrical, a digital multimeter is required. A 12 volt lead acid battery, as used in cars and trucks, will indicate 12.6 volts with a DVM. A battery that measures 12.0 volts is 75% discharged. A digital volt meter is a great electrical test tool. Even the very cheapest digital meter will give lots of valuable information. A battery voltage that is low will not "excite" an alternator to begin a charging voltage of about 14.7 volts. The alternator voltage must be higher than battery voltage. To determine if there are any phantom electrical loads on a battery, connect a horn or any 12 volt lite between the battery negative post and the battery cable. If the lite come on or the horn beeps, there is a load. By unplugging and removing lite bulbs and disconnecting the wires to the alternator, the battery drain may be located. The only acceptable load is the clock, whichs rewinds the clock very quickly. The most common loads are the alternator, heater motor, trunk and glove box interior lites...... Frank __________________ Chevy stepper 400sb 350 turbo Last edited by Frank-id; 11-26-2003 at 08:57 PM.