Voltage problem

[Donkitsontj]

I am having a voltage issue... I'll be driving along and voltage will drop to nothing.... it's left me stranded a couple of times but once I jump start it the voltage returns to normal... usually for an hour or so...
I've had the battery tested and it is good...
I've had the alternator tested and it is also good...
I've heard it could be in the PCM but they want $175. To reflash it... I just hate to spend that kind of money without knowing for sure....
Thank you in advance for any help!

 

[Jerry Bransford]

How are both ends of both battery connecting cables? Are they in good condition and bright and shiny CLEAN on the inside where it counts?

 

[Donkitsontj]

How are both ends of both battery connecting cables? Are they in good condition and bright and shiny CLEAN on the inside where it counts?

Yes I replaced both cable terminals and wire brushed everything else...

 

[qslim]

I had a similar problem last year - at random times voltage would drop to nothing, light would dim... Usually only lasted a few seconds. I had everything tested with no discrepancies found. My battery cables were new.. I started by changing the battery even though it was testing fine while on the tester and the problem disappeared. It looked to be about 3 years old according to the sticker on it.

 

[Jerry Bransford]

I've had the battery tested and it is good...

Ok at this point I'm going to say take it to a different battery specialty shop and have them perform a Load Test. Not everyone who conducts a load test knows WTF they're doing, trust me on that. I absolutely KNEW my Toyota's battery was bad so I went up to my local usual battery shop to buy a replacement. They had a new guy who insisted on doing a load test and I noticed he didn't hold the test on long enough. He pronounced the battery good and said I didn't need one. I then turned to the guy I knew and had him do another load test and he held the load on long enough for the test to be valid... and it definitely confirmed that the battery was toast.

Have it load tested by someone who knows what they're doing and insure the load is applied continuously for 15 seconds. And the load needs to be half of the battery's CCA rating.