International VT 275 V6, Руководство пользователя

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ECM Relay Circuit Operation
• The ECM controls its own power up
and power down process. When
the key is OFF, the ECM stays
powered up for a brief period. The
ECM then powers down after
internal housekeeping functions
have been completed.
Key Power
• The Run/Accessory position of the
key switch receives battery voltage
from the Power Distribution Center
(PDC) fuse F-12. When the key is
ON, the switch supplies battery
voltage through fuse F46 to ECM
pin X3-3. Battery voltage is
available at all times through fuses
F4 and F41 to ECM relay pins 1
and 3. The two fuses are in series,
with F4 feeding both the IDM and
ECM relays, and F41 dedicated to
protecting the ECM circuit alone.
Pin 1 supplies voltage to the
relay coil.
• Pin 2 connects the coil to pin X3-5
of the ECM.
• When the key is ON, voltage
supplied to pin X3-3 signals the
ECM that the operator is going to
start the engine. The ECM then
supplies a ground circuit to pin X3-5.
When this occurs, current flows
through the ECM relay coil and
creates a magnetic field causing
the relay to latch. When latched, the
relay connects pin 3 to pin 5 and
supplies current to the ECM
through pin X4-1 and X4-2.
Shut Down
• When the key is OFF and voltage is
removed from ECM pin X3-3, the
ECM shuts down the engine but
keeps the ECM powered up briefly
until the internal house keeping is
completed.
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International ® VT 275 V6 Engine
ELECTRONIC CONTROL SYSTEM
ECM
BATTERY
200 A F4
F-46
TO IDM RELAY
TO
ENGINE
INLINE
12-WAY
F41
F-12
R
PDC
1
STARTER
MOTOR
RELAY
KEY SWITCH
PDC#
F4
F12
F41
F46
R
Device
30A...IDM/ECM
20A...RUN/ACC
10A...ECM PWR
5A...ECM KEY PWR
ECM RELAY - POSITION 50
X1
X2
X3
X4
X1
X2
X3
X4
X3-3 V
IGN
X3-5 ECM MPR
X4-1 ECM PWR
X4-2 ECM PWR
1
5
2
3
1