Table 4-2. Unit Troubleshooting-continued -706880243

TM 5-4210-233-14&P-1

Table 4-2. Unit Troubleshooting - Continued

MALFUNCTION

TEST OR INSPECTION

CORRECTIVE ACTION

ELECTRICAL SYSTEM - HI-IDLE CIRCUITS - Continued

REAR SWITCH WILL NOT DISENGAGE HIGH IDLE - Continued

Step 6. Check aerial circuit breaker#5 for +12V.

Replace aerial circuit breaker #5 (see para 4-99).

Step 7. Check for +12V at high idle switch (wire #1222).

Replace wire 1222 between breather and switch (see para 4-9.4).

RUN/LOCK LEVER WILL NOT DISENGAGE HIGH IDLE WHEN IN "LOCK" POSITION

(Refer to Electrical Wiring Diagrams, Appendix H, Sheet 9 of 16.)

Step 1. Check that aerial master switch is on.

Turn on aerial master switch.

Step 2. Attempt to disengage high idle with rear switch.

If high idle disengages with rear switch, go on to Step 3.

If high idle does not disengage with rear switch refer to "rear switch will not engage high idle

with parking brake on and transmission selector in N (neutral)."

Step 3. Check limit switch at run/lock lever for proper operation.

Replace run/lock lever limit switch (see para 4-185).

Step 4. Check "off " timer for proper operation (a +12V signal applied to wire 1304 should produce

a +12V signal on wire 1134 for 1/2 second).

Replace "off" timer (see para 4-9.4).

REAR PANEL "DO NOT ENGAGE HIGH IDLE UNLESS LIGHT IS ON" LIGHT WILL NOT

ILLUMINATE WITH PARK BRAKE ON AND SHIFT SELECTOR IN N (NEUTRAL)

(Refer to Electrical Wiring Diagrams, Appendix H, Sheet 9 of 16.)

Step 1. Check bulb.

Replace bulb (see para 4-178).

Step 2. Check CRY032 (park brake relay) for proper operation.

Replace CRY032 (see para 4-9.4).

Step 3. Refer to high idle circuit troubleshooting procedures.

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