I have a 2015 Viper LTX MCI turbo fails to start

[Bluebullet]

I have a 2015 Viper LTX that has been brought to me to see if I can find the issue. Sled cranks fine, fuel pump comes on and pressurizes and shuts off. codes active are: P1689 (rev ckt low), P1692 ( fwd ckt low), P0562 (sys volt low) also the R is showing on the dash and backup buzzer alarming. I replaced the battery with and new one as the negative post was broken off. ( obvious issue) I have checked all the fuses and removed and reinstalled all the relays. ( no obvious corrosion). I cleaned and reinstalled the two ground wires above the primary clutch. This sled also has the MPI turbo modification. Lots of loose wiring job not tied down, looks like a 12 year old wired! The ECU was updated flashed by a dealer last year. Ran fine for 1 ride after dealer worked on the sled. All of these codes are related to the ISC Ckt as best I can tell. Is there a way to clear those codes without getting it to start! Looking for some help please!
Blue

 

[Bluebullet]

I have a 2015 Viper LTX that has been brought to me to see if I can find the issue. Sled cranks fine, fuel pump comes on and pressurizes and shuts off. codes active are: P1689 (rev ckt low), P1692 ( fwd ckt low), P0562 (sys volt low) also the R is showing on the dash and backup buzzer alarming. I replaced the battery with and new one as the negative post was broken off. ( obvious issue) I have checked all the fuses and removed and reinstalled all the relays. ( no obvious corrosion). I cleaned and reinstalled the two ground wires above the primary clutch. This sled also has the MPI turbo modification. Lots of loose wiring job not tied down, looks like a 12 year old wired! The ECU was updated flashed by a dealer last year. Ran fine for 1 ride after dealer worked on the sled. All of these codes are related to the ISC Ckt as best I can tell. Is there a way to clear those codes without getting it to start! Looking for some help please!
Blue

Moving on down to look at the ECU wiring. Man that thing is not easy to get to! How do I get the sled in diagnostic mode to reset codes? any help is appreciated!
Merry Christmas!

 

[Bluebullet]

Figured out the diagnostic mode through gage pod ( didnt help). All tests are good going into the ECU nothing coming out..... ordered a used spare ECU for reasonable cost.

 

[MrSled]

Figured out the diagnostic mode through gage pod ( didnt help). All tests are good going into the ECU nothing coming out..... ordered a used spare ECU for reasonable cost.

Thats a strange one. I would think a new battery would have done it.