HYDRAULIC SUSPENSION LOCKOUT WILL NOT ENGAGE (HMMH) (REG. NO. UC053E THRU UC053K) cont'd -680640368

TM 5-2420-224-20-1

Table 3-5. Troubleshooting (Cont)

Malfunction

Test or Inspection

Corrective Action

ELECTRICAL SYSTEM (CONT)

Step 3. Check for +24 VDC between wire (6) and ground at D+ relay (7).

+24 VDC is not present, go to step 35.

+24 VDC is present, go to step 4.

Step 4. Check for +24 VDC between wire (8) and ground at control switch (5).

+24 VDC is not present, go to step 22.

+24 VDC is present, go to step 5.

Step 5. While holding control switch (5) completely out, check for +24 VDC between

wire (9) and ground at control switch.

If +24 VDC is not present, replace control switch (5) by

removing wire (8), wire (9), wire (10), knob (11), nut (12), and

control switch.

If +24 VDC is present, release control switch and go to step 6.

Step 6. Check for +24 VDC between wire (10) and ground at control switch (5).

If +24 VDC is not present, replace control switch (5) by

removing wire (8), wire (9), wire (10), knob (11), nut (12), and

control switch.

If +24 VDC is present, go to step 7.

Step 7. Check for +24 VDC between wire (10) and ground at solenoid relay (13).

If +24 VDC is not present, repair wiring (10) between control

switch and solenoid relay.

If +24 VDC is present, go to step 8.

Step 8. Check wire (14) at solenoid relay (13) for continuity to ground.

If open to ground, go to step 11.

If short to ground, go to step 9.

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