Table 4-2. Unit Troubleshooting-continued -706880242

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

CAB SWITCH WILL NOT DISENGAGE HIGH IDLE

(Refer to Electrical Wiring Diagrams, Appendix H, Sheet 3 of 16.)

Step 1. Check that aerial master is off and RUN/LOCK lever on aerial panel is in LOCK position.

Turn off aerial master, place RUN/LOCK lever in LOCK position.

Step 2. Check latching relay (CRY031) for proper operation. Relay should disengage when +12V is

applied to terminal #8 (Wire 1134).

Replace CRY031 (see para 4-9.4).

Step 3. Check for +12V at circuit breaker on ignition accessory buss.

Replace breaker (see para 4-99).

Step 4. Check high idle switch for proper operation.

Replace high idle switch (see para 4-94).

REAR SWITCH WILL NOT DISENGAGE HIGH IDLE

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

Step 1. Check that aerial master is on.

Turn on aerial master switch.

Step 2. Check that RUN/LOCK lever on aerial panel is in LOCK.

Step 3. Attempt to disengage high idle using cab switch.

Refer to "cab switch will not engage high idle with parking brake on and transmission

selector in N (neutral)."

Step 4. Check rear control panel high idle switch for proper operation.

Replace switch (see para 4-179).

Step. 5. Check wire 1134 for continuity between high idle switch and terminal #8 on CRY031.

Replace wire (see para 4-9.4).

4-113