Nilfisk-Advance 7765 Service Manual page 121

Service Manual – Advance 7765 / Nilfisk CR1500
Troubleshooting
Problem
Main broom motor
not running.
Specifications
Component
Hydraulic Broom Drive Motor
Main Broom Solenoid (2) Valve
Cause
Circuit breaker CB6 is
tripped.
No voltage to the Main
Broom Solenoid (2) valve.
Main Broom Solenoid (2)
valve not operating correctly.
Specifications
Displacement – 4.5 CIR
Voltage – 12 volts
Nominal Coil Resistance – 7.2 Ohms
Initial current draw – 1.67 amps
Correction
Reset the circuit breaker.
• Check for continuity through the hopper and
hopper door "whisker" switches when the hopper
is down and the hopper door is closed. Repair the
wiring or replace the switch(es) as necessary.
• Check the Main Broom Switch function and repair/
replace as necessary.
• Check the wiring from the Main Broom Switch to
the Main Broom Solenoid (2) valve. There should
be 0 volts to the solenoid when the main broom
and dust control motors are off, and 12 VDC to the
solenoid when the motors are on.
1. Check the solenoid coil resistance. If not 7.2
ohms ±10%, replace the coil. Also see the
Broom Sweep System Wiring
2. If the coil resistance is within spec, check for
binding or a mechanical problem. Repair or
replace the solenoid valve as necessary.
Sweep System, Main Broom
Main
Diagram.
226