TM 5-2420-231-23-1
0073
Table 1. Multiple Backhoe Operations (Pilot Controls) Do Not Function Correctly - Continued.
073
MALFUNCTION
TEST OR INSPECTION
CORRECTIVE ACTION
5. Operate backhoe swing, dipper,
Backhoe Operates Normally -
Multiple Backhoe
Proceed to step 6.
boom, and bucket (TM 5-2420-
Operations (Pilot Controls)
231-10). Monitor and record
Backhoe Swing, Dipper, Boom, and
Do Not Function Correctly -
machine operation.
Bucket Operate Slowly or Will Not
Continued
Operate - Proceed to Test Step 21.
Backhoe Dipper and Boom Will Not
Operate - Proceed to Test Step 26.
Backhoe Dipper Operates With Left-
Hand Joystick and Boom Operates
With Right-Hand Joystick (Pattern 2)
- Proceed to Test Step 26.
6. Operate left and right stabilizer
Left and Right Stabilizer Cylinders
Operate Normally - Proceed to step 7.
down (TM 5-2420-231-10). Moni-
tor and record machine operation.
Left and Right Stabilizer Cylinders
Will Not Operate - Proceed to Test
Step 28.
7. Operate backhoe control pattern
Pilot Control Pattern Switch Off
(Pattern 2) - Troubleshooting complete.
switch to pattern 2 (TM 5-2420-
231-10). Monitor and record
Control Pattern Switch Illuminates -
Replace control pattern switch (WP
machine operation.
0189).
Proceed to Test Step 29.
Test Step 2. Check Pilot Controller
Indications.
Monitor and record indicator on the pilot Indicator Flashes On for 3 Seconds
control controller (WP 0007, Figure
Then Off Less Than 1 Second
160) (WP 0006).
Continuously (Normal) - Replace pilot
control switch (WP 0189).
Proceed to Test Step 29.
Indicator on Pilot Controller Off -
Proceed to Test Step 3.
Test Step 3. Test for Faulty Pilot
Controls Fuse.
1. Turn ignition switch to the off posi-
tion (TM 5-2420-231-10) and dis-
connect batteries (WP 0157).
2. Remove pilot controls fuse (TM 5-
2420-231-10).
Resistance 5.0 Ohms or Less - Install
3. Using a digital multimeter, mea-
pilot controls fuse (TM 5-2420-231-10).
sure resistance between terminals
Proceed to Test Step 4.
of pilot controls fuse. Resistance
should be 5.0 ohms or less.
Resistance Greater Than 5.0 Ohms -
Replace pilot controls fuse (TM 5-2420-
231-10).
Proceed to Test Step 10.
0073-3
