No start. 2014 Cascadia. Ultrashift. J1939 No trans code on dash. Fuse? Please help.

Have a 2014 Cascadia with ISX and a ultrashift that gets used seasonally. Went to start it a week ago and it was 100% dead. Tossed the charger on it for a few hours turned key on and not enough juice to start but no code. Charged a few more times and no dice and then the J1939 code No trans showed up. So it wouldn't even try to crank. Pulled the batteries and they were only 2 years old and they tested so low they said it almost has to have a drain or a short. Hooked up the new batteries with the hot cables and then checked with a test light and sure enough there is a short. Not sure where to go from here? Any ideas?

 

The J1939 terminating resistor is located behind the radio near the windshield.

 

Thanks for the reply. I wonder if "no trans" means it's not detecting the transmission. Or does that mean its transmitting info with that J1939 resistor?

 

I’d say it’s not transmitting, no transmission wouldn’t keep it from starting

 

Well I did a little more digging and found a blown 30 amp fuse under the hood. It's labled as "TCU, BAT". Popped in a new fuse and it blew as soon as I put it in. Hoping someone here can help me out it's dead in the water right now and can't even get it to the shop. Hoping it's an easy fix but I can't find what is shorting and causing the blown fuse.

 

Power supply to transmission TCM may be rubbing on metal. TCM bolted to driver side of transmission. Will have 2 square plugs that look identical. Try to concentrate on harness towards front of truck. Cut zip ties, open split loom and observe. Warning. It will probably be a tight squeeze to fit up in there to do all of this.

 

no trans will keep it from starting.... the ecm must get a signal from the trans (trans in neutral for safety) before it will alow it to start

Like a neutral safety switch on a car

 

hm, never had an issue with that, most my vehicles never had that, new pickup will but no issues there, hadn’t thought of neutral switch

 

Every auto car/pu I've had newer then 1970 has required it be in N or P to start... even the standard 3,4 & 5 speeds required the clutch be pressed to start..

 

I suspect water in a harness connector causing the fuse to blow immediately and also a short to GND somewhere like what was mentioned earlier.

If you can supply last 6 of vin, I can point towards what circuits on the PDM and where to check.