New Holland CX720 Repair Manual page 1874

A-01 =ENGINE CONTROL UNIT (ELEC)
K-39=GRID HEATER RELAY (IVECO)
F-01=ECU POWER FUSE
ENGINE
ECU Power Supply
The CX840, CX860 and CX880 combines are equipped with engines that utilize electronic controllers to control the
fuelling systems on the engines. The Engine Control Unit (ECU) has a special startup and shutdown procedure re-
quired for proper operation.
When the key is first turned on, all other modules receive power through the key switch, causing them to "wake up"
and start functioning. When CCM2 first "wakes up", it immediately applies power to connector X016 pin J2-13. This
power travels through the wire harnesses to the ECU connector X193 pin 15, signaling the ECU to "wake-up". The
ECU then connects the ground path for the coil of the ECU Power relay K-14, causing the relay to energize and
provide main power for the ECU at connector X193 pins 3 & 4, as well as for the grid heater relay K-39.
If the operator turns the key off, or activates a "kill-stall", the CCM2 module shuts off power at connector X016 pin
J2-13, which cuts off the power supply to the ECU connector X193 pin 15. When this power supply is lost, the ECU
starts its "shut down" routine, including saving files and operating information to memory, and shuts down the engine
fuelling system to stop the engine. After several seconds, the ECU disconnects the ground path for the ECU Power
relay K-14 coil, and the relay unlatches, stopping main power supply to the ECU.
POWER PRODUCTION - FUEL AND INJECTION SYSTEM
K-14=ECU POWER RELAY
R-09=ENGINE GRID HEATER (IVECO)
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