Voltage question
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Voltage question
I've been watching my Prodigy P3 brake controller lately since it has the ability to display voltage while I'm driving.
Wat I'm seeing is a voltage of no higher than 13.7 and each time I have my foot in the pedal even just a little bit and the injectors are doing their work, I see voltage usually between 12.2 and 12.8. When the AC is running is when I see the lower 12's. As soon as I let my foot off of the pedal, it pops up to lower to mid 13's in voltage.
The other thing that I am noticing is that the longer the trip is, towards the end of the trip has the lowest voltage reading average. It's like a downward trend in voltage the longer I am driving and it's harder for the voltage to recover after throttle.
Anyone have any ideas if this is remotely normal or an indication of either weak batteries or weak alternator or both?
Thanks,
Drake
Wat I'm seeing is a voltage of no higher than 13.7 and each time I have my foot in the pedal even just a little bit and the injectors are doing their work, I see voltage usually between 12.2 and 12.8. When the AC is running is when I see the lower 12's. As soon as I let my foot off of the pedal, it pops up to lower to mid 13's in voltage.
The other thing that I am noticing is that the longer the trip is, towards the end of the trip has the lowest voltage reading average. It's like a downward trend in voltage the longer I am driving and it's harder for the voltage to recover after throttle.
Anyone have any ideas if this is remotely normal or an indication of either weak batteries or weak alternator or both?
Thanks,
Drake
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I think the cables are good. One thing I noticed tonight after looking under the hood is that 4 hours after last using the truck, the alternator is still quite warm to the touch. Would this be evidence of simply it working over-time to make up for bad batteries or is my alternator on it's way out?
Thanks,
Drake
Thanks,
Drake
Logistics Pro
Joined: Apr 2010
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From: Panama City, FL
Ck ur alternater in the morning after its been sitting all night and see if its still warm, if so then I would say the diode in the alternater is bad. Take it in and get it bench checked. If it cks good then u have a drain somewhere else.
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It was a bad alternator. Had an extra Ford alternator laying around that I picked up from a salvage yard, dropped it in and viola! No more excessive engine noise, no more engine stutter, better throttle response right off of idle, headlights and turn signals brighter, less engine noise, engine runs smooooooth!
Voltage is behaving as expected now on my brake controller voltage read-out.
I had no idea a bad alternator can wreak so much havok on these trucks.
I also was having issues with the truck running crappy just before it rained or stormed out. I will have to see if that still continues, but I doubt it seeing how much improvement this has already made to my trucks problems.
I'm truly amazed!
Drake
Voltage is behaving as expected now on my brake controller voltage read-out.
I had no idea a bad alternator can wreak so much havok on these trucks.
I also was having issues with the truck running crappy just before it rained or stormed out. I will have to see if that still continues, but I doubt it seeing how much improvement this has already made to my trucks problems.
I'm truly amazed!
Drake
Post Fiend
Joined: Sep 2003
Posts: 6,096
Likes: 26
From: Mesa AZ
It was a bad alternator. Had an extra Ford alternator laying around that I picked up from a salvage yard, dropped it in and viola! No more excessive engine noise, no more engine stutter, better throttle response right off of idle, headlights and turn signals brighter, less engine noise, engine runs smooooooth!
Voltage is behaving as expected now on my brake controller voltage read-out.
I had no idea a bad alternator can wreak so much havok on these trucks.
I also was having issues with the truck running crappy just before it rained or stormed out. I will have to see if that still continues, but I doubt it seeing how much improvement this has already made to my trucks problems.
I'm truly amazed!
Drake
Voltage is behaving as expected now on my brake controller voltage read-out.
I had no idea a bad alternator can wreak so much havok on these trucks.
I also was having issues with the truck running crappy just before it rained or stormed out. I will have to see if that still continues, but I doubt it seeing how much improvement this has already made to my trucks problems.
I'm truly amazed!
Drake
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I am fairly certain that the voltage regulator on these have a two speed circuit to them. One charging circuit for lower rpm and one for higher rpm. I have never studied it really hard but that was how it was explained to me quickly one time when i had one that would charge at idle but throw a light and quit charging at highway speed.
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