TM 5-6115-593-12
TO 35C2-3-463-1
Table 4-3. Organizational Troubleshooting-Continued
MALFUNCTION
TEST OR INSPECTION
CORRECTIVE ACTION
10. ENGINE WILL NOT START IN COLD WEATHER-continued
If S2 is not defective, the ether aid control relay K24 (part of AC-DC control relay assembly, 18,
figure 4-19) or the ether solenoid (14, figure 4-39) may be defective. The ether solenoid can be
replaced as part of the ether kit (see paragraph 4-65). Relay K24 must be referred to next higher
level of maintenance for testing or replacement.
Step 3.
Check WATER TEMP gauge. Coolant temperature should read between 60 and 110°F (16° and 43°C).
If temperature is below range, proceed to next step.
If temperature is within range, the preheat system is functioning normally and malfunction must be
referred to next higher level of maintenance.
Step 4.
Use a multimeter to check for 120V AC across the coil of preheat contactor relay K107 (54, figure 4-12).
If 120V AC is present, proceed to next step.
If 120V AC is absent, test PREHEAT SYSTEM switch S105 (27, figure 4-13) and replace if
defective (see paragraph 4-22).
If S105 is not defective, check run/stop relay K1 (7, figure 4-19) for 24V DC across contacts 3 and
4.
If 24V DC is present K1 may be defective and should be referred to next higher level of
maintenance for testing.
Step 5.
Test preheat contactor relay K107 according to paragraph 4-23.
Replace K107 if defective (see paragraph 4-23).
If K107 is not defective, proceed to next step.
Step 6.
Test heater contactor K109 (54, figure 4-12) according to paragraph 4-23.
Replace K109 if defective, (see paragraph 4-23).
If K109 is not defective, proceed to next step.
Step 7.
Test thermo immersion switch, S30 (13, figure 4-30A) according to paragraph 4-51.
4-29
