I have had weird electrical problems with the truck for years.  But never let me down except original vp44 crapped out a year in a half ago and replaced it. My belt snapped in my driveway Recently and I needed to get new battery as well so I decided to inspect clean or replace a few grounds and do a few things on the truck. Battery, 2 new terminals, oil filter change and fuel filter change add a new fp gauge sensor and buy all new fuses for the truck while Inside and out and new tensioner because it was worn out. Did fluids first started truck with old belt ran perfect for a min and belt came off again so i shut it down immediately.  then i disconnect batts and started removing fuses and did everything except tensioner since I couldnt find a long enough ratchet at the time. Hooked everything back up and now truck wont start. It blew #3 fuse in pdc the first time i tried starting it and The vp won't kick on and right after wts light the  first time the check engine light pulls up with  p1693 and p1694. after that i only get code no comm from buss to vp44. Cleared code and it comes right back I been slammed with work so my next move is wt mod but I did all new grounds with copper ends flux solder and heat shrink and all accessory power lines the same except the harness grounds in the wt mod, Dr side engine ground, And ground right above starter. All relays and fuses are good lift pump kicks on fine and i have power and ground to vp pump.  I don't know if the auto shut off is telling or not to kick on or if there is a bad connection in my PDC some where.  I checked all grounds i replaced they where good. I want to hard wire the vp and tap ignition to see if it kicks on and maybe it's a wiring harness issue or I'm taking the ecm and pcm and getting them  repaired if it's not the pump. Also checked all connectors in pdc with power probe for positive or negative confirmation for all fuses and relays and the asd fuse top left blade when ignition is on goes in and out. I Can give any info on continuity ground open or closed circuits and volts if needed for you guys. I Need help I'm stumped......

Edited March 4, 20232 yr by 99dodgecram

checking for voltage at pump and gonna follow a couple wires to see if something shorted out. anybody have pinout for the ecm plug?

It's still possible there is an issue. If the wait to start is flashing like he said in this morning phone call that means something is wrong. I suggested checking power and ground pins on the ECM and contact Auto Computer Specialst. Yup he called this morning for help.

3 hours ago, 99dodgecram said:

anybody have pinout for the ecm plug?

It's in the FSM section 8W-80-40 connector pin outs, page 1053.  You'll fined the FSM in the down load section of this web site.

https://mopar1973man.com/files/file/215-1999-ram-fsm/

thank you guys so far it has power and good grounds. same as vp44. codes coming up are p0123 p1388 p1689 p1693 after disconnecting batteries and reconnecting & clearing codes the wait to start light stopped and only p1388 and p1693 are left. Im guessing the ASD is signaling the cutoff and/or testing ohms for th2 communication signals from vp44 connector to ECM connector. 

Edited March 25, 20232 yr by 99dodgecram

wait to start light is flashing again with no check engine light on. p0123 p1388 p1693 p1694.

Edited March 27, 20232 yr by 99dodgecram

P1694 code is communication problem. Without looking I would say ECM.

 

https://mopar1973man.com/cummins/articles.html/24-valve-2nd-generation_50/51_engine/obdii-error-codes_94/p1694-no-bus-message-received-from-companion-module-r139/?do=getLastComment&d=4&id=139

 

i have 2 shorts they said apps pin 15 and 12v to pump pin 25. i tested the pump and it has almost 13v so idk what else to do im sending it back to them tommorrow i called today they where cool about it I told them everything i replaced and done so far and they said if the tune is off they will fix it and if there is anything wrong wit software tune and they can tell mewhat is coming up again to try to rediagnose.

found short in apps harness no3 0 volts with key off or on

You still need to look into the communication error problem.

ordered new apps evn tho i installed the current one in 12/22 Sending the ECM & PCM back tomorrow to get tested pretty sure the tune is messed up on it. I guess they have a test truck hopefully its a 98.5 they will test it on. Also had truck towed to a buddys shop today cant do the wires since im colorblind and dont want to mess anything up with the harness now. this will be the fun trying to explain to these mechanics what i already did and am not paying for them to redo what has already been done. Handing over the wiring schematics and all the info I have done so far. bummed out the color blind **** limits me from time to time like this and now i gotta waste money on something i could of done myself if i could see normally.....

3 hours ago, 99dodgecram said:

ordered new apps evn tho i installed the current one in 12/22

I've got the Timbos APPS in the store...

 

https://store.mopar1973man.com/dap-commercial-grade-throttle-position-sensor-tps9804.html

so i got the ecm back again and the tune is correct narrowed it down to one code for the no starting. my wait to start doesnt kick on and there is p1689 buss failure. what should i do now?

No Wait To Start no ECM. Check fuses. That is the first instruction is to light the Wait To Start.