alarm 35 on MOD 5 = Undervoltage/overvoltage protection has operated.
There has been a real undervoltage situation or there is a fault in the hardware section.

There is a HPK service gram from cat about this alarm 35 on all mod's
first it says to check the battery, make sure the battery is fully charged and there are no issues with any cells, all connections are tight and good.
Note: during voltage drop test the voltage should NOT drop below 30v.

also check for voltage drop across K1 and K2 contactors. Put your meter leads across the contactor tips. The contactor should be open, if you read move than 1v across either then replace the K2 contactor.