Nilfisk-Advance Captor 4800 - Scrub System; Troubleshooting Guide; Scrub Deck Will Not Lower; Part A: Electrical Control Circuit

FORM NO. 56043093 / Captor
™
4300, 4800, 5400 - 43
SCRUB SYSTEM
TROUBLESHOOTING GUIDE
Possible Symptom
1 Scrub deck will not lower
Part A: Electrical Control Circuit
Note: Do all testing with the key switch ON, scrub deck pressure set on (1) by depressing the scrub decrease switch on the A2 display panel.
Scrub deck will not lower (1)
Press and hold scrub
decrease switch (-).
Is its green indicator light on?
Substitute a new A2
display panel.
Does the deck lower?
Check for 12 volts at coil
• L4 (+) ORG (-) YEL/BLU.
Repair or replace
defective coil wiring.
Does the deck lower?
Check for coil resistance
at L4 (9 ohm)
Replace defective coil.
Does the deck lower?
See Hydraulic scrub deck
troubleshooting section Part B
position 1.
Yes
Yes
Yes
No
No
No
Press scrub off switch then scrub
decrease switch (may need to be
cycled to observe lights) observe the
green lights on the A1 board S3 & S4
are they on.
Replace A1 control
board.
Does the deck lower?
No
Yes
No
No
No
No