I have a 99 cummins and it started to cut out at high rpms I though maybe it was the lp wo I did a volt test and it was putting out 13.1 volts checked the fp ar idle its sitting at 15psi changed fuel filter then added lucas additive. Yesturday my radio quit working but still has lights on it no dome light and no power to the diagnostics port if checked all the fuses they are all good. I have been told it could be a bad diode in the alt putting out ac noise and iv also been told bad ecm. I do have an issue with with my positive cables on batteries always getting super corroded not long after I clean them. I need some help here before I go dump a pile of money in this thing.

Did you check cables below drivers batter to see if they're loose.

 

From sounds of it you need to get good crisp battery connections going.

 

You might also check battery voltage with cables unhooked.  One battery might read 12.4 and the other 10 that's no good.

 

I'd also check battery connection on starter its probly loose with 10 years of mud and oil on it..

 

Does cruise control work?? 

2 hours ago, Evan said:

Did you check cables below drivers batter to see if they're loose.

Are you talking about the grid heater solenoids?

2 hours ago, Evan said:

Did you check cables below drivers batter to see if they're loose.

Are you talking about the grid heater solenoids?

No the cruise control doesnt work it turns on but won't set. But I did just redo all the battery connections I'll check the starter and under the driver side battery

I'm also guessing the converter is locking and unlocking at cruise speeds in both 3rd and 4th.

 

My hunch now that your cruise control is wacky is that you are nearly having voltage issues. 

 

The cable connections below the drivers battery I honestly dont know what they are but I know them being loose caused me to have similar issues as you.

 

You need to go through and clean every battery connection on the truck wether you think it pertains to your issues or not.

 

I asked about the cruise control because I had granny issue where my torque converter wouldnt hold cruise also didnt work.

 

Regardless wether your computer is bad these issues need to be looked into and can often be fixed for free. 

My truck is a manual 5 speed so no I'm not having those issues.  But I did wake up this morning and the iod fuse was blown again even though i didn't drive my truck after rrdoingvthe terminals on my battarey cables. I only started it for a minute

Ol wo new update I changed the iod fuse this morning and while driving to work down a rough dirt road I hit a bump and it blew again this truck is driving me insane ?

1 hour ago, Rigtruck92 said:

new update I changed the iod fuse this morning and while driving to work down a rough dirt road I hit a bump and it blew again this truck is driving me insane ?

 

Fuse 12...

So it would have to be a short in one of those lights or the data link connector

The lights are wire hot constantly so it possible you have a bare spot in a wire somewhere. I would be looking for the last hack job a previous owner might have done to the truck. So it will be the pink wire for sure. The other side goes to ground and just lights the light up for you. 

Edited August 14, 20186 yr by Mopar1973Man

Ok so there is not light under the hood but the wires were there loosely and just kind of hanging what'sthe chances of it bouncing and making a connection then blowing the fuse ? I cut them back so they couldnt touch any thing 

I would cut them back so no bare copper was shown then taken a small wire nut and capped out the wires. This will guard the very tips from touching. 

Ok I'll get them capped I think that could be the issue there was about 9" of wire hanging never really dawned on me to cut them back. Electrical is such a pain in the ?lol

I feel your pain.  

I put a volt meter on the teuck again with the proper meter and it was ranging between .019 and. 007

So batteries are unhooked 

1 minute ago, Evan said:

So batteries are unhooked 

No they where hooked up and running they had 13.94 to each 

Both batteries when running will read the same. Check each battery independent unhooked from the truck.

 

What's .019volts ?

There are capacitors and stuff those like mopar man know alot about. I just know that's turned off  lol

 

2 minutes ago, Evan said:

Both batteries when running will read the same. Check each battery independent unhooked from the truck.

 

What's .019volts ?

There are capacitors and stuff those like mopar man know alot about. I just know that's turned off  lol

 

He is testing for stray AC voltage from the alternator. Too much can cause issues.

Ohhh ripple. Definitely a topic for other. Could check ground continuity to frame while volt meters out

51 minutes ago, Rigtruck92 said:

I put a volt meter on the teuck again with the proper meter and it was ranging between .019 and. 007

Thats a passing voltage. I have never seen that wide a spread on mine. I was around .03 on mine and @W-T's ground mod dropped me down to .01. Worth while to do.

Yes I will be doing that soon