Eaton Fuller Advantage (2017) Fault Code: 37 PID: SPN: 627 FMI: 5 Power Connect: Current Below Normal or Open Circuit

Overview:
The Fuller Advantage transmission is equipped with electronic components that require a high current. It is critical that the OEM power supply be able to deliver the proper voltage and current in these high-load situations for smooth and efficient shifting. Additional resistance introduced into the system can cause the supplied voltage to drop low enough to cause performance issues. Fault Code 37 indicates an excessive resistance between the power supply source (battery or starter) and the Transmission Electronic Control Unit (TECU).

Detection:
The TECU monitors the OEM power supply circuit for excessive resistance by measuring the voltage drop during high current demands, such as a shift request, and calculates a resistance value based on those demands. Fault Code 37 sets Active when the calculated resistance during high-load conditions exceeds 0.4 ohms and the TECU has not detected any low or weak battery system faults.

Conditions to Set Fault Code Active:
FMI 5 – Current Below Normal or Open Circuit: TECU calculates a resistance value based on high current demands and sets the fault code Active when that resistance exceeds 0.4 ohms.

Fallback:
No fallback mode is associated with this fault; however, transmission performance issues may be presented.

Conditions to Set Fault Code Inactive:
TECU calculates a resistance value below 0.4 ohms.

Possible Causes:
FMI 5
1) Vehicle Power Supply
– In-line fuse corrosion or loose connection
– Wiring shorted to ground, shorted to power or open
– Bent, spread, corroded or loose terminals
2) Vehicle Batteries
– Internal failure or high resistance