THROTTLE CONTROL SWITCH WILL NOT OPERATE (HMMH). -680640393

TM 5-2420-224-20-1

Table 3-5. Troubleshooting (Cont)

Malfunction

Test or Inspection

Corrective Action

ELECTRICAL SYSTEM (CONT)

Step 1. Check for +24 VDC between wire 70M (1) and ground at auxiliary throttle

switch (2).

If +24 VDC is not present, repair wiring 70M between auxiliary

throttle switch and connector X.

If +24 VDC is present, go to step 2.

Step 2. With auxiliary throttle switch (2) in CRANE position, check for +24 VDC

between wire 73V (3) and ground at auxiliary throttle switch.

If +24 VDC is not present, replace auxiliary throttle switch

(page 4-156).

If +24 VDC is present, go to step 3.

Step 3. With auxiliary throttle switch (2) in CRANE position, check for +24 VDC

between wire 73V (3) and ground at tool switch (4).

If +24 VDC is not present, repair wiring 73V between auxiliary

throttle switch and tool switch.

If +24 VDC is present, go to step 4.

Step 4. With auxiliary throttle switch (2) in CRANE position, check for +24 VDC

between wire 73V (3) and ground at throttle control switch (5).

If +24 VDC is not present, repair wiring 73V between tool

switch and throttle control switch.

If +24 VDC is present, replace throttle control switch

(page 4-158).

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