Hi All,

(2001 DRV 3500 5.9)
Is voltage drop from 14.3 to 13.9 (across battery terminals) at idle speed when HVAC blower fan is turned to high “normal” or might I have a problem? Once up to speeds over 35 mph this drop does not occur.

There is no or very slight drop at the lower blower motor speeds at idle or with any other electrical accessories turned on. I have a new alternator and new external voltage regulator.

thanks in advance

 

High blower is a pretty high draw, so, a bit of a drop doesn't seem out of line. Probably normal.

 

I haven't even seen 13.9 without any draw so I would say that isn't too bad.

 

Long story short it looks like my original in dash volt meter is screwed up. I'm using one that plugs into the cig. lighter socket for now.

Thanks for your responses.