Fault Code Guide

f544724
Chassis
Module
Bulkhead
Module
AMU/AAVA
Solenoid 1
AMU/AAVA
Solenoid 2
PUMP
399A
399
399C
399B
02/22/2012
J1939
Smart
Switch
Pressure
Feedback
Switch
Solenoid
Coil
Pressure
Feedback
Switch
Solenoid
Coil
NOTES:
• Pump functions require two solenoids to shift the transfer case. Solenoid 1 provides air when power is applied to the
solenoid coil (normally closed). Solenoid 2 provides air when power is removed from the solenoid coil (normally open).
• The pressure switch closes when air pressure reaches about 12 to 28 psi (83 to 193 kPa).
• Only the feedback from the pressure switch in the normally closed solenoid is used by the pump control system. The
other circuit is wired, but is not used.
Fig. 4, Typical Wiring Diagram of a Split Shaft PTO
PTO and Pump Electrical Controls 54.38
Specifications
Business Class M2 Workshop Manual, Supplement 22, September 2012 400/3