Replaced Battery / Alternator - Voltmeter shows occasional discharge

[mmesa005]

As the title of the thread states the voltmeter is showing a discharge from time to time, mostly when the engine is warmed up, in drive, idling at a stop light. I have cleaned all the battery connections and the battery is new as is the alternator. Both were checked as good.

Any ideas as what to check next would be greatly appreciated!

 

[JerryC]

Need more info. What are the voltages, what is on at the time? Lights, blower, etc?
Idle rpm?

 

[3rd Petal]

Did it do this before you put the new alternator in as well, or just since the new alternator and battery was put in?
Might be fairly normal if it is just doing it at idle. I know on my B2, if I let it sit idling with a few accessories on the alternator barely puts out what the truck is drawing. Just cause the alternator isn't spinning fast enough at idle to make a lot of power