2015 Cat 279d electrical issue

[bentleynv]

Stumped! I have a 2015 CAT279D I charged the battery overnight on a slow AGM trickle charger as i have done many times before but this time and next morning i had no screen display, no beep, no fuel pump. So i have tested the fuse panel and no voltage. I checked the main fuses-good I checked power to ignition switch-no power to BAT terminal. I checked the Large studs behind the cab and had 12v. I checked the smaller studs below the 6 mega fuses. They were readings of 12v -0v 12v-0v 12v -0v....strange. I fused jumped the six studs together...now i had power to the fuse panel...still no power to the BAT terminal on the ignition switch. I removed the jumpers and tried to jumper the ignition switch BAT terminal...no change. I am about to blow a fuse myself! Any ideas? Help!

 

[rodby554]

Stumped! I have a 2015 CAT279D I charged the battery overnight on a slow AGM trickle charger as i have done many times before but this time and next morning i had no screen display, no beep, no fuel pump. So i have tested the fuse panel and no voltage. I checked the main fuses-good I checked power to ignition switch-no power to BAT terminal. I checked the Large studs behind the cab and had 12v. I checked the smaller studs below the 6 mega fuses. They were readings of 12v -0v 12v-0v 12v -0v....strange. I fused jumped the six studs together...now i had power to the fuse panel...still no power to the BAT terminal on the ignition switch. I removed the jumpers and tried to jumper the ignition switch BAT terminal...no change. I am about to blow a fuse myself! Any ideas? Help!

Sounds like a classic broken circuit somewhere between the main fuses and the switch. Have you checked the relays? Sometimes they stick or get corroded enough that they won't trigger even if the battery is sitting at 12v.