New Holland CX720 Repair Manual page 1372

Dome light - Problem solving (A.40.A.23 - G.40.A.30)
OPERATION
Interior lighting consists of a switchable Dome Light with LH Door Switch, Time Delay Module and side lights mounted
on each mirror. The Dome Light has an integral switch that can be set in the off, dome or door position.
When the Dome Light switch is set in the door position, the light will illuminate when the driver's door is opened. When
the LH Door Switch is closed a ground signal is provided to illuminate the Dome Light and activate a 60 second timing
cycle in the Timer Delay Module. The Time Delay Module looks for a "change of state" and will power the side lights
mounted on each mirror anytime the LH Door Switch is opened or closed. The timing cycle will be deactivated when
ever the Ignition Key is in the "RUN" position.
Unswitched power is provided to the Dome Light so it can be operated at any time by placing the Dome Light Switch
in the dome position.
The Dome Light switch can be placed in the off so that the Dome Light will not illuminate even when the door is
opened.
Illumination lights in the vehicle are controlled by the CCM and RHM. The CCM receives a signal from the Road Light
Switch indicating that the switch has been placed in the "PARK" or "RUN" position. A signal is also sent by the CCM
to the RHM indicating the position of the Road Light Switch. Power to the illumination lights is supplied by the CCM
and RHM and will operate them at full intensity during the daytime or at a lower intensity for nighttime operation of
the vehicle.
Power is applied to the Horn Switch at all times. The Horn Switch is integrated in to the Road Light Switch. When the
operator closes the Horn Switch contact, current flows through the Horn Switch to operate the horn.
Refer to : Wiring harness - Electrical schematic frame 27 (A.30.A.88 - C.20.E.27)
Refer to : Wiring harness - Electrical schematic frame 28 (A.30.A.88 - C.20.E.28)
Refer to : Wiring harness - Electrical schematic frame 29 (A.30.A.88 - C.20.E.29)
Refer to : Wiring harness - Electrical schematic frame 30 (A.30.A.88 - C.20.E.30)
Refer to : Wiring harness - Electrical schematic frame 42 (A.30.A.88 - C.20.E.42)
Refer to : Wiring harness - Electrical schematic frame 43 (A.30.A.88 - C.20.E.43)
Refer to : Wiring harness - Electrical schematic frame 44 (A.30.A.88 - C.20.E.44)
Refer to : Wiring harness - Electrical schematic frame 45 (A.30.A.88 - C.20.E.45)
Refer to : Wiring harness - Electrical schematic frame 23 (A.30.A.88 - C.20.E.23)
Refer to : Wiring harness - Electrical schematic frame 24 (A.30.A.88 - C.20.E.24)
Refer to : Wiring harness - Electrical schematic frame 36 (A.30.A.88 - C.20.E.36)
Refer to : Wiring harness - Electrical schematic frame 35 (A.30.A.88 - C.20.E.35)
TROUBLESHOOTING
Before troubleshooting the Interior Lighting and Horn System, make sure that the following operating conditions
are met:
A. The batteries are fully charged, and all connections are clean and tight.
B. Transmission in neutral or park.
C. Check all connectors for full installation, loose, corroded, pushed out or bent terminals.
D. Fuses F-51 and F-52 are good.
NOTE: The batteries must be fully charged and all connections clean and tight. Use a multimeter (DVOM) for these
tests.
DISTRIBUTION SYSTEMS - LIGHTING SYSTEM
2 4/7/2006
A.40.A / 56