Battery voltage
Junior User
Joined: Jan 2007
Posts: 86
Likes: 0
From: East Tennessee
Wow, where are you doing your testing? The batteries should be in parallel and read 12.4ish when not ving charged. If under a charge and the glow plugs are not activated then they should read in the 14's.
Junior User
Joined: Jan 2007
Posts: 86
Likes: 0
From: East Tennessee
It sounds like the batteries are hooked in series and not parallel. At the +- terminals of one of the batteries it should read 12 ish. I would think you would be havings some terrible problems.
Posting Guru
Joined: Apr 2009
Posts: 2,447
Likes: 1
From: Northern Idaho
Driver's side battery:
Negative to Body or engine
Positive to Positive of Passenger's side battery
Passenger's side battery:
Negative to body or engive
Positive to starter or distribution block
I am doing this from memory and that is why I say "or" but as they said, if you have 24v then you are WAY over volting your system and you are taking a chance on frying equipment including your PCM, IDM, stereo, anything in the rig as most can't handle much over 18v
Batteries when the vehicle is off should be about 12.1 to 13.9. 13.9 is after a fresh charge, 12.1 is after sitting for a few hours or more, 12.5 is preferred.
13.2 to 14.2 is a normal running range. 13.8 is the preferred voltage (Engine running).
If you are at 24v then your positive on battery A is tied to the negative on battery B and your negative on battery A is tied to the body of the vehicle and B is tied to the starter.
(WARNING)Fix your problem before you burn something up or burn your truck down.
Negative to Body or engine
Positive to Positive of Passenger's side battery
Passenger's side battery:
Negative to body or engive
Positive to starter or distribution block
I am doing this from memory and that is why I say "or" but as they said, if you have 24v then you are WAY over volting your system and you are taking a chance on frying equipment including your PCM, IDM, stereo, anything in the rig as most can't handle much over 18v
Batteries when the vehicle is off should be about 12.1 to 13.9. 13.9 is after a fresh charge, 12.1 is after sitting for a few hours or more, 12.5 is preferred.
13.2 to 14.2 is a normal running range. 13.8 is the preferred voltage (Engine running).
If you are at 24v then your positive on battery A is tied to the negative on battery B and your negative on battery A is tied to the body of the vehicle and B is tied to the starter.
(WARNING)Fix your problem before you burn something up or burn your truck down.
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Posting Guru
Joined: Apr 2009
Posts: 2,447
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From: Northern Idaho
Do you need to know the specific locations? If so I'll get you some pictures.
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Junior User
Joined: Jan 2007
Posts: 86
Likes: 0
From: East Tennessee
No no, I was aking the original poster to look at his setup. He obviously had his wired in series to get 24 volts. I would say there are some other things not working if there is not a system in place to protect the electronics.
Yes, your post is right. Positive to positive and negative to negative (or ground).
Cargo Master
Joined: Jun 2003
Posts: 3,292
Likes: 6
From: Ardenvoir, Washington
Remove the positive cable from one battery and test your voltage off the battery terminals.. to check your tester..
Or.. check the voltage on another vehicle if you can to double check the voltage tester...
Or.. check the voltage on another vehicle if you can to double check the voltage tester...
Hotshot
Joined: Jan 2002
Posts: 17,988
Likes: 207
From: La La Land
His meter is AFU.
Pop
Junior User
Joined: Jan 2007
Posts: 86
Likes: 0
From: East Tennessee
I just think it is odd that his meter would be off by a multiplier of 2 (unless he was reading with a oscilloscope and had a X2 probe on the unit 
). You would think if the meter was an issue then it would probably not be reading an exact double of what it should be. Considering it would be easy (having one of the batteries turned around backwards allowing the terminals to be opposite of the cable sides) to hook them up in series and get 24 volts. He has not been back since his original posts. Hope everything is ok.
). You would think if the meter was an issue then it would probably not be reading an exact double of what it should be. Considering it would be easy (having one of the batteries turned around backwards allowing the terminals to be opposite of the cable sides) to hook them up in series and get 24 volts. He has not been back since his original posts. Hope everything is ok.
Hotshot
Joined: Jan 2002
Posts: 17,988
Likes: 207
From: La La Land
If you turn one of these batteries around, you will NOT have a 24 volt battery, you will have a huge short, and you'll INSTANTLY know it! POW!
This is not what his mis-reading is caused by.
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