TM 9-2320-260-20
Table 2-4. Electrical Troubleshooting (Contd).
MALFUNCTION
TEST OR INSPECTION
CORRECTIVE ACTION
Test 2. Test air horn solenoid voltage.
Step 1. Remove lead 25 from pin B of air horn solenoid.
Step 2. Touch negative lead of multimeter to frame ground.
Step 3. Touch positive lead of multimeter to pin B of solenoid.
a. If voltage is present, go to test 3.
b. If voltage is not present, go to step 4.
Step 4. Remove lead 25 connected to pin A of air solenoid.
Step 5. Touch negative lead of multimeter to frame ground.
Step 6. Touch positive lead of multimeter to contact end of lead 25.
a. Replace air horn solenoid if voltage is present (para. 4-30).
b. If voltage is not present, repair or replace lead 25 (para. 4-52).
Test 3. Test horn switch input voltage.
Step 1. Remove horn switch (para. 4-29) until lead 25 can be seen.
Step 2. Set multimeter to a voltage range that will measure 24 volts.
Step 3. Touch negative lead of multimeter to frame ground.
Step 4. Touch positive lead of multimeter to lead 25 contact end.
a. Repair or replace lead 25 if voltage is not present (para. 4-52).
b. If voltage is present, go to test 4.
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