JLG 80HX_HX+6_HXER ANSI Service Manual - Manual (Page 67)

SECTION 3 - CHASSIS & TURNTABLE
3120271 – JLG Lift – 3-29
Troubleshooting
We will discuss Troubleshooting in two general catego-
ries:
• Governor won’t work.
• Governor works, but can’t be set up to give satisfactory
performance.
There is, of course, some overlap between these catego-
ries. Read both sections and apply the fixes that seem
appropriate.
NOTE: During troubleshooting, be prepared to control the
engine manually to prevent overspeeds, etc.
• Governor won’t work.
No reaction from Governor. Actuator output arm never
moved, engine off or engine running. Can be caused by:
1. No power.
2. Incorrect linkage, preventing movement.
3. Incorrect electrical hook-up.
4. No speed signal to Governor.
5. Damaged Controller or Actuator.
(1.) No power - Use a multimeter to check for 12-15 VDC
between terminals A & B on the controller. Check during
engine off and engine running conditions. If voltage is
absent or low, check for:
a. Wiring error.
b. Hook-up on wrong side of ballast resistor.
c. Low battery.
d. Bad voltage regulator.
e. Bad ground connection.
f. corroded terminals.
g. Undersized wiring.
(2.) Incorrect Linkage - Re-check linkage as discussed on
page 40 and 41. Freedom of movement and lack of play
are important.
(3.) Incorrect Electrical Hook-up - Re-check all wiring and
connections to the Actuator and Controller against the
supplied schematic.
(4.) No speed signal to Controller.
a. Check the voltage between terminals C and
ground and D and ground of the 8 pin connector
with the engine running. You should see 5 - 30
VDC.
b. The above checks do not guarantee a good
speed signal, but their absence proves that
there is a problem.