Ford Powerstroke Diesel Forum banner
1 - 14 of 14 Posts

·
Registered
Joined
·
3 Posts
Discussion Starter · #1 ·
I have a 2005 F250 powerstroke with a 195,000 miles and the truck will go dead in three days. I have replaced the batteries twice and still have the problem. in each battery I have 14.5 volts. I cleaned all the connections to the ground and power side of both batteries but it still goes dead in three days. I have 9.5 volts going to the ground. All the conponents work except the hood light when raised. I have to put the battery charger on it everynight. I have checked the altinator which I replaced two years ago I pulled the ground off while it is running and continues to run which tells me the altinator is good. I dont know what the problem could be? Could this be the GEM Module? I have checked everything else I can think of. If anyone has any suggestions or help would be greatly appreciated. Thank You Bill
 

·
Compression Ignition Addict
Joined
·
10,212 Posts
As an fyi - the Instrument Cluster sends the charge signal to the alternator (you don't have a GEM per se).
 

·
Premium Member
Joined
·
4,512 Posts
What is the voltage reading at cold after three days of sitting?
 

·
Premium Member
Joined
·
4,512 Posts
I meant what's the battery voltage after it's been sitting for three days?
 

·
Premium Member
Joined
·
3,361 Posts
After an overnight, put your hand on the alternator and a hand on the GPCM carefully. If one is warm (or hot), you've usually found your issue for a drain like that.

GPCM's can go bad and keep the glow plugs on.
 
  • Like
Reactions: Bornsilly9

·
Registered
Joined
·
39 Posts
I had an similar issue with my Lexus Rx300. The cause was my 2yr old son turning every knob to the on position.

Here's how you look for a parasitic draw. Remove children, frisk for any tools they may be holding. Disconnect all the unnecessary stuff drawing power in the cab. Hook a volt meter; dialed to Miliamps up in series; between the batt ground and the battery. This will show the draw in miliamps. Start with the highest range and dial it back. Then start pulling fuses and see which circuit is the offender. You can use a known good vehicle as a reference for what the draw should be.

That's all I got for that. It's a bit of a goose hunt.



C
 

·
Premium Member
Joined
·
4,512 Posts
I usually start with anything aftermarket. Stereo. Alarm. Etc. Not uncommon that they're the culprit. Shorted alternator (as mentioned) also not uncommon.
On a truck like yours, expect to see around 100ma give or take, once all modules have gone into sleep mode, which can take anywhere from a few minutes to half hour or so.
 

·
Registered
Joined
·
4,759 Posts
ook a volt meter; dialed to Miliamps up in series; between the batt ground and the battery. This will show the draw in miliamps.
I will only add to disconnect one battery totally when doing this. Two batteries in parallel may not get a correct milliamperes reading.

You also need to find a way to keep the truck from coming out of sleep mode when you open the door to pull fuses. There’s a switch that on some cars can by rigged to think the door is still shut, but don’t know how that works with our trucks. May just take longer to enter sleep mode if you leave the door open.
 

·
Premium Member
Joined
·
3,361 Posts
Again, before you go crazy doing all of that work, do the two quick checks of the alt and GPCM.
 
1 - 14 of 14 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top