Posted by Sherman in Idaho [72.47.153.105] on Monday, December 23, 2013 at 16:03:33 :
In Reply to: OT, slightly.....Beware Of AutoZone posted by Randy On Long Island [63.117.245.163] on Monday, December 23, 2013 at 15:22:18 :
Much safer and equally simple test is just put a voltmeter on the battery posts see what you get, idling and revved up. I won't bother repeating what means what here, but if they can trust the autozone "technician" with a wrench, and the ability to find the battery cable, they can trust him with a voltmeter and the ability to interpret it correctly.
I don't suppose there's such a thing as a published calibration procedure for the voltage function in the DIC display. No, these days everybody thinks if it's digital it has to be perfect, even though it's measuring an analog thing.
On the other hand, where did you check it with your meter, and where does the DIC check it? If you checked right at the battery, and the DIC is measuring it somewhere else, it could be 1.1 volt lower there, due to a bad connection someplace. When I'm doing the quick electric check for anybody, I have them turn the lights on to see how bright they look and to see how much the battery voltage drops, checking between the fuse block and chassis ground in that case. That's an easy test to see if any of the battery cables, grounds, etc are suspect, before going to all the trouble of disconnecting and cleaning it all up. Modern vehicles have very undersized wiring, to save weight, and even with all the connections "good", a drop of a volt or so between battery and load is not uncommon.
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