Lull 944E-42 Service Manual - Manual (Page 542)

Electrical System
9.32 Model 644E-42/944E-42 Rev. 6/04
Testing for Electrical Intermittence
Perform the following procedure while wiggling the
harness from side to side. If possible, continue this at
6-inch intervals while watching the test equipment.
• Testing for Short to Ground
• Testing for Continuity
Testing Relays from the Fuse Block
Relays are used to control a large amount of current by
using a small amount of control current flowing through
the relay coil.
1. Be sure the vehicle is on a level surface, the
implement grounded, parking brake engaged,
ignition switch is in the OFF position
2. Unlock and open the engine cover.
3. If the vehicle has dual batteries, disconnect both
negative battery cables (1 and 2) from both
batteries.
To access the lower battery (3), loosen the knob (4)
far enough so that the lip (5) on the upper battery box
clears the knob. Lift up the upper battery box (6) and
swing it out, so that the box clears the hydraulic tank
support bracket, to gain access to the lower negative
battery cable (1). Disconnect the lower negative
battery cable.
4. Remove the cover plate (7) from the right side
console (8).
5. Remove the plastic cover (9) from the fuse and relay
block.
6. Refer to the relay location chart, on page 9.22, for
the location of the relays within the fuse block.
7. Remove the suspect relay from the vehicle.
8. Apply the proper voltage to the relay coil at
terminal 86 (10 and 12) and attach the ground (-)
probe to terminal 85 (11 and 13), ground. An audible
click should be heard indicating that the relay is
functioning properly.
MU0650
1
2
3
4
5
6
OU0670
8
7
9
86
85
30
87
87A
MN1820
10
11