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Cranks But Wont Run Need Help Help

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2.2K views 5 replies 2 participants last post by  jerrybbc  
J
#1 ·
last saturday night my 03 3500 cummins 4x4 6spd stick as i'm driving home @ 2AM (45min drive) my check gauge's light came on then as i looked my battery gauge went all the way down 5 min into the drive I still kept on driving about 30 min later still driving then my radio turns off but that's it so i keep driving then 5 min later my lights stat to go dim ( now i think i'm only running on batteries only ) but i keep on driving I want to get home about a mile and a half away from home my lights are only a glow then my truck shakes like its going to die a block away but i manage to go up the drive way ran 2 stops because i thought is i stopped it would stay there as im in the drive it is ideleing but rough and no lights I turn it off then leave the batteries charging over night (OPTIMA RED TOPS 1 1/2 yr old) sun around noon i take the charger off and go to startbit up and it fires right up batteries fully charged and the voltage gauge is still down so i start to disconect the batteries to check the alternator output and the truck dies. I reconect the batteries and think its the alternator but as I go to start the truck nothing happens it just cranks hard. The instument panel all gauges are down but lights will come on and radio i dont hear the lift pump prime(LP was replaced by dealer 20,000 miles ago,all new injectors and tubes about 10k ago, turbo and waste gate 500 or so miles ago all under warranty) now the truck cranks but wont turn on/run any ideas or help would be aprecciated thanks It has about 5/8's of a tank I have checked and rechecked all fuses on the IPM and even changed it out and there is no diffrence there is no power to the ODM ar it does not power a MATCO code reader or the Bully Dog as if you are not turning the key to the run position I am waiting for a wireing diagram of the ECM to see if it has a good ground and power coming in and going out other than that Im lost stumped anyone with some similar expirience anything :confused013::banghead::banghead::confused013::S::confused013::banghead::banghead::confused013:
 
#3 ·
have the alternator tested at a local parts place autozone o'reillys advance auto parts whatever.

There is no internal regulator in 3rd gen trucks. If the alternator is bad, swap it out. If it tests good, then you need to look at the command line from the ECU to make sure it is getting a signal to charge. No signal out either means a bad connection or a burned up ECU
 
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#4 ·
Taking the batteries out of the circuit like that on new cars isn't a good idea because it can cause a voltage spike that can burn up electrical components. There weren't many sensitive electrical components back in the day, but semiconductors are a lot more fragile than what they used to be. It can cause a load dump of up to 140 volts depending on how hard the batteries are charging at the time. Do you have any chip installed on the truck? most of those don't have load dump suppression and can burn up from that spike. Most of the on board components from the factory are protected.
 
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J
#5 ·
yes the alternator is bad I took it to a alternator/starter specialty shop they showed me it has no output so this is part of the problem butnot all the truck should still fire up with fresh batteries in it and the gauges should at least move but they dont and now i do know that if your car or tuck is newer than a 85 you should not discoonect the batteries while the engine is runinng to be on the safe side mon I should get the alternator back but still hhave no clue what else to check and i dont really want to take it to the stealership b/c if they say its the ECM they said 2k-2500 R&R to much $$$$ I can get a reman ECM for $595.oo plug-N-play no need to flash with the same 1yr warranty as stealership i do have the BULLY DOG TD on since the truck was about 3mo young that I use on performance mode and once in a while on CRAZY LARRY i talked to BULLY DOG about the possability of loosing the program and they said if they cant get it back they would down load it agian GREAT PEOPLE
ANYMORE IDEAS COME ON :banghead::banghead::confused013::confused013::banghead::banghead: I CANT BE THE ONLY ONE THIS HAPPEND TO
 
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