Alternator or Battery?
starcarguys
10-30-2007, 02:56 PM
'97 Suburban 4x4 LT 1500
Noticed that my voltage guage likes to read below 14 volts when running. When I first start up, it sits at 14, but then reads around 13 on the guage. My headlights seem to be dimmer then normal. Never have any problem cranking/starting even after sitting for a day or so. Does this sound like an alternator or battery issue?
Noticed that my voltage guage likes to read below 14 volts when running. When I first start up, it sits at 14, but then reads around 13 on the guage. My headlights seem to be dimmer then normal. Never have any problem cranking/starting even after sitting for a day or so. Does this sound like an alternator or battery issue?
j cAT
10-30-2007, 05:07 PM
'97 Suburban 4x4 LT 1500
Noticed that my voltage guage likes to read below 14 volts when running. When I first start up, it sits at 14, but then reads around 13 on the guage. My headlights seem to be dimmer then normal. Never have any problem cranking/starting even after sitting for a day or so. Does this sound like an alternator or battery issue?
load test battery first, this is a large grid resistor that is applied across the battery, should stay in good zone. test for free at battery store.If good and or problem is same could be both bad. measure with accurate voltmeter the alt. . should read with engine running and all lights on at alternator red output lead 14.5 volts engine hot if very cold could go up to 15volts.Now if you know someone who has an amp-probe meter you can check alternator output current . this should be 70amps approx. of course thats with a good battery fully charged. thats it good luck
Noticed that my voltage guage likes to read below 14 volts when running. When I first start up, it sits at 14, but then reads around 13 on the guage. My headlights seem to be dimmer then normal. Never have any problem cranking/starting even after sitting for a day or so. Does this sound like an alternator or battery issue?
load test battery first, this is a large grid resistor that is applied across the battery, should stay in good zone. test for free at battery store.If good and or problem is same could be both bad. measure with accurate voltmeter the alt. . should read with engine running and all lights on at alternator red output lead 14.5 volts engine hot if very cold could go up to 15volts.Now if you know someone who has an amp-probe meter you can check alternator output current . this should be 70amps approx. of course thats with a good battery fully charged. thats it good luck
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