Hey fellas

 

Started diag on a battery drain today.

Seems when I disconnect the alternator the drain goes from 480mA to under 50mA ........ how do I determine if I have a bad ground on alternator an open circuit ..... or just a bad alternator.

 

Just to answer that.

I had the batteries tested - 1 was bad and one was good. I already knew this thats why I isolated the passenger among other things (bad). So now I have new alternator, new passenger battery and a good drivers.

I will run through the pulling fuse exercise again ....... and will capture a video of part of it ........ but yeah its pretty much what I have already done.

I looked and you didn't really mention what was disconnected when you did the other fuse pulling.  I'm saying disconnect the positive battery terminal and everything on those 2 lugs, then bridge between battery positive and one of the lugs and then start pulling fuses. If you did exactly that then ok, if you had stuff hooked up such as things on the terminals then I would be a little suspicious and do it again the way I said, that way we remove all doubt. 

not sure if  anyone  has  checked theirs...  but  what is  considered  'normal'..  with  stuff like the  radio (clock),  security,  and  anything else always  'hot'?

edit;   just remembered (from my  flatbed install last week),   the  12v supply to  trailer.     That isn't keyed,  I remember  seeing a fuse for it  in the  pdc...  but   that's a lot of  wire (CHECK YOUR TRAILER PLUG TOO)   A little mud in the socket...  ya never know!

Aftermarket  brake controller?

Edited December 8, 201410 yr by rancherman

IOD I *think* is 50MA from factory.

Unsure with non factory radio and some other stuff .........

No aftermarket brake controller.

 

Im sure when we track it down l'll feel like more of an idiot ...... but its not jumping out at me

Edited December 8, 201410 yr by JOHNFAK

Need to get pass the alternator lugs and get into the subsystems and start measuring other circuits for draw. The lugs at the alternator fuse are the master feeds entering the vehicle anyways. As I supplied in the pic in the previous post. Heck if your out here in Idaho I'd do the testing for you.

Hey,  FMI,    are the  circuits  (within the cab  fuse panel)  hot  'after' the  pdc?  ie;   is  the cab  fuse  panel  separate from the   pdc     

Am I correct  on  the  fuses in the cab  are  for   sensing/gauge/and  exciter type circuits,  whereas  the   underhood  panel is  for the  'work'  circuits?

 

 

 

Once again the is the PDC. Everything under the hood is usually exterior circuits. The fuse panel inside the cab is going to be all cab related.

I am missing  (or  am  too  schematic dumb)  to see the  path  of  juice to the  in-dash  fuses.   I see  where is comes  from  via  keyed  circuit..  but  at the top of the  page is  cut off  (bottom  diagram).    How  does  this  tie in to the   top  diagram?

 

edit...   maybe this is it?    'top diagram'....     circuit  at extreme top of page has    'A'  labeled inside a triangle    'to fuses  in  diagram  2 of  3'   ???

Edited December 8, 201410 yr by rancherman

Top pic fuse 2 & 10 supply the circuit for the key switch. Fuse 1 supplies also to the Cab. There is 3 pages of power supply for this.

 

 

2002-Dodge-Cummins-Wiring.pdf

OK found it ---- plus also the reason why I missed it the 1st run.

 

ELECTRIC POWERED SEAT FUSE (BIG SILVER FUSE).

 

Reason I missed it was if you are monitoring it and pull the fuse ...... it still shows 0.5A on the circuit at the 140A lug after pulling fuse.......... you have to short the circuit (scratch/spark until the energy is gone) ad then it drops to 4.5mA (~0A).

 

 

So before I button this ll back up .......... do I need to do any more diagnostics or any ideas on how to determine why the powered seats are drawing at key off.

Well for now I would just unplug the electric seats.

 

But what's funny I've happen to have a electric seat switch here for you if need be...

 

 

But more than likely you have a bad power seat switch.

How quickly will 0.5A draw drain a good battery system. As I suspect that the main draw for the dead batteries was the bad battery - not this ....... but still wanted to track down.

 

Also - how do you diagnose a bad switch for power seats. 

This page should give you an idea.

http://www.interstatebatteries.com/content/product_info/marine_f.asp

 

Ed

If he doesn't need that switch, I do. Mine's smashed & I jsut put the seat in the best position with alligator clip leads.

I don't "Need" it, but it would be nice.

 

Ed

How quickly will 0.5A draw drain a good battery system. As I suspect that the main draw for the dead batteries was the bad battery - not this ....... but still wanted to track down.

 

Also - how do you diagnose a bad switch for power seats. 

 

Check for draw. Since you passing power into the seat motors some how draining on the batteries then the switch must be making a weak connection.

 

You could unhook each seat motor one at a time to see which switch could be causing it. When you find the motor that is bleeding the current then when it unhooked the draw will vanish.

Be sure to check the wires for rubbing on the seat, there's a good possibility you could have a wire rubbed through and grounding out just enough to start pulling a load on the circuit.

friggin  electric seat! 

Glad ya found it man!

friggin  electric seat! 

Glad ya found it man!

 

Talk about sitting in the "Hot Seat!"

Good job, John! Congrats on locating it. They can be a royal PITA (like you found out)!

And, you've been sitting on this problem for how long? Ha  ha.... oh...

 

Ed