OK I'll start with my truck is a 99 24v auto. All stock aside from a beans sump and a fass 150. I had a edge ez but it's been removed. Also I just replaced the vp44 with a used vp44. Before I replaced it I had a hard set p1689 no communication between ecm and vp44. Once I put the replacement VP in the code immediately went away and right before I had all the injectors bled(almost had it running) it threw the p1694 in both ECM and PCM and then kicked me out of the bus connection. Still have power at the data link connector. 

Now I'm unable to connect my scanner(Autel Maxidas) to either, no tach signal while cranking, no wait to start light, no lift pump signal, and pin 7 on the vp44 isn't getting power. Likely because the fuel pump relay isnt getting the correct signal. If we put power to the wire from the FP relay that goes to pin 7 on the vp44 we can hear the VP click on. I've tested all fuses and grounds with my power probe 3 and all test good. I pulled the ECM plug and tested all the pins and it's getting correct power and ground from pins 48,49,50. I did notice all pins related to Cummins bus showed no signal or anything on the power probe. Pins 40 and 41 show 0.0 with key off and a little over 2v with key on. I may be making this harder than it should be but I'd like to rule out any other possibilities before replacing the ECM... Any help is greatly appreciated.

Nope. Problem hasnt gotten worse or better. 

With everything off check all fuses and see if there is any draw that should tell you what's draining the battery, some timers may stay on for few hours after ignition is off. Sorry that's all I know. 

Ill have to bring the test light home tomorrow and check for draw again. Did this a while back and found a large draw from the shorted out seat belt in the drivers seat. However this truck is like the base model, no power windows, no power locks, no power seats(seat belt has power), ive pulled the dome light, both door sensors, and the glove box light. Will check in the morning to see if batterys are dead or not.

I'm guessing the seatbelt power is so the airbag works

7 minutes ago, Dieselfuture said:

I'm guessing the seatbelt power is so the airbag works

Seat belt light on the dash.

1 minute ago, dripley said:

Seat belt light on the dash.

 I was thinking airbag won't go off unless it knows you're wearing a seatbelt, but I think we're both right. 

2 minutes ago, Dieselfuture said:

 I was thinking airbag won't go off unless it knows you're wearing a seatbelt, but I think we're both right. 

Mine was stuck on for a long time. Put the new.to me seats in and it went off. I believe the air bags will go off no matter what unless you turn off the passanger side switch then it want go off. 

I know you will find the problem. Start pulling one fuse at a time and see which one stops the draw. 

 

I'm a bit slow on electrical but w/ a good volt meter there is a way to set it up to see the amount of electrical load or draw on the batteries. I think the meter has to be able to read amps draw or load and is hooked up between the positive battery post and the removed battery clamp.

 

Hoping someone will chime in here, but with a proper set up Volt Meter you will be able to pull fuses and/ or relays one at a time and find it readily.

Well batteries werent completely dead but they didnt have enough juice to turn the truck over fast enough to fire. Going to check for draw tonight. Not sure if the draw is related to the ecm turning off though.

seat belt light is the only light that is on on my dash

 

Stupid computer BS 

 

 

.

4 minutes ago, GSP7 said:

seat belt light is the only light that is on on my dash

 

Stupid computer BS 

1

 

Easy fix either wear your seat belt or jump the little plug on the driver side. Light off. No computer involved unless the you have the version with the center seat module for locking the seat belt in the seat. Even then that module only control the locks of the belts not the light. 

What controls the light then?

7 minutes ago, dripley said:

What controls the light then?

 

Driver seat belt. That all. There is 2 wires that run up into the seat belt latch to detect when the selt belt has been inserted to the latch. Then the switch turns off the lgiht. Nothing more. 

Edited April 18, 20186 yr by Mopar1973Man

5 minutes ago, Mopar1973Man said:

 

Driver seat belt. That all. There is 2 wires that run up into the seat belt latch to detect when the selt belt has been inserted to the latch. Then the switch turns off the lgiht. Nothing more. 

That's what I thought. Missunderstood what you said previously.

  Yes I have the center seat module for locking the seat belt in the seat.

 

I have seat belt lock module plug in connector wired with a bypass so the belts dont lock

 

Do you hav a trick to get the dash light to stay off? 

 

2 seat belt latch wires on the drivers side only somewhere? Where exactly ? inside the seat? colors?

 

  And yes I wear the seat belt so cops wont pull me over.

Edited April 18, 20186 yr by GSP7

Driver seat latch there is two wires just jump them. 

I just checked my Drivers seat latch next to the center seat counsel and there are no wires to the latch at all on my '99.

 

Just a bare latch , No Wires or harness or inside switch at all

 

Maybe the '99 is different far as the wires in the latch. I read up on it and I know dodge deleted the stupid design belt lock module under the center seat, and stupid belt lock solenoids in 2000 IIRC

 

 

.

 

Edited April 18, 20186 yr by GSP7

So will airbags go off no matter what then as long as front sensors say so, even with seatbelt off.

They should unless you turn the passenger side off.

7 hours ago, GSP7 said:

I just checked my Drivers seat latch next to the center seat counsel and there are no wires to the latch at all on my '99.

 

Just a bare latch , No Wires or harness or inside switch at all

 

Maybe the '99 is different far as the wires in the latch. I read up on it and I know dodge deleted the stupid design belt lock module under the center seat, and stupid belt lock solenoids in 2000 IIRC

2

 

I wish I had more information on that stupid module it only ran a few years and that never really made it to the FSM books. Kind of like the fly by wire cruise didn't make the book either. (Lazy Dodge FSM Book writers...)