TM 9-6115-729-24
0013
ELECTRONIC TECHNICIAN (ET) TROUBLESHOOTING - Continued
CORRECTIVE ACTION - Continued
c.
Set Battery Disconnect Switch to ON. Set DEAD CRANK SWITCH to
NORMAL. On EMCP set ENGINE CONTROL switch to COOL
DOWN/STOP.
(1) If the voltmeter indicates zero volts, ensure that the circuit breaker is not
tripped.
(2) Check the harness from the battery to the air inlet heater relay. Make
(3) Retest and ensure the voltmeter measures 24 +/- 3.0 Vdc.
e. On EMCP set ENGINE CONTROL switch to OFF/RESET. Set Battery
Disconnect Switch to OFF. Set DEAD CRANK SWITCH to OFF.
STEP 10.
Check for voltage output at the air inlet heater relay.
a. Reconnect the wire from the +battery to the air inlet heater relay.
b. Remove the wire to the air inlet heater from the air inlet heater relay.
c.
Connect a voltmeter between the output terminal of the air inlet heater relay
and engine ground (Figure 1).
d. Set Battery Disconnect Switch to ON. Set DEAD CRANK SWITCH to
NORMAL. On EMCP set ENGINE CONTROL switch to COOL
DOWN/STOP.
e. Observe the voltmeter. The voltmeter should indicate zero volts, since the air
inlet heater relay is not energized. If the voltmeter shows 24 +/- 3.0 Vdc,
ensure that the voltmeter is connected to the output side of the air inlet
heater relay.
f.
Run the Air Inlet Heater Override on the Cat ET and observe the voltmeter.
NOTE
The Air Inlet Heater Override has a one minute timer in order to disable the test when the time
expires.
g. On EMCP set ENGINE CONTROL switch to OFF/RESET. Set Battery
Disconnect Switch to OFF. Set DEAD CRANK SWITCH to OFF.
h. If the voltmeter did not measure 24 +/- 3.0 Vdc, replace the air inlet heater
STEP 11.
If the problem is not resolved, check the wiring between the air inlet heater relay
and the air inlet heater (Figure 1).
a. Reconnect the wire from the air inlet heater relay to the air inlet heater.
b. Disconnect the wire between the air inlet heater relay and the air inlet heater
from the air inlet heater side.
0013-5