Table 4-2. Unit Troubleshooting - Continued
TEST OR INSPECTION
ELECTRICAL SYSTEM - HI-IDLE CIRCUITS - Continued
REAR CONTROL PANEL HIGH IDLE SWITCH WILL NOT ENGAGE HIGH IDLE
(Refer to Electrical Wiring Diagrams, Appendix H, Sheet 9 of 16.)
Check that parking brake is engaged.
Engage parking brake.
Check that transmission selector is in N (neutral).
Place transmission selector in N (neutral).
Check that aerial master switch is ON.
Turn aerial master switch ON.
Attempt to engage high idle with cab switch.
If high idle engages with cab switch, go to step 2.
If high idle does not engage with cab switch, refer to "cab switch will not engage high idle
with parking brake on and transmission shift selector in N (neutral)."
Check rear control panel high idle switch.
Replace switch (see para 4-179).
Check for +12V at aerial buss.
Refer to "+12 volts not present at aerial master buss" troubleshooting procedure.
Check for +12V at circuit breaker #5 on aerial master buss.
Replace breaker (see para 4-99).
Check for +12V at switch (wire 1222).
Replace wire from breaker to switch (see para 4-9.4).
Check wiring for continuity.
Replace wire (see para 4-9.4).