TM 3-4230-218-30&P
2-2.
SYMPTOM INDEX.
Malfunction
No.
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
Malfunction
Page
Burner lights and extinguishes when the
START BURNER switch is released . . . . . . . . . . . .2-2
Burner will not extinguish when THERMOSTAT
SELECTOR switch is set to OFF (OPEN MAG
VALVE light is off). . . . . . . . . . . . . . . . . . . . .2-4
Burner will not extinguish when THERMOSTAT
SELECTOR switch is set to OFF (OPEN MAG
valve light is on) . . . . . . . . . . . . . . . . . . . .2-4
Burner will not liqht. . . . . . . . . . . . . . . . . .2-4
Engine knocks or backfires . . . . . . . . . . . . . . . 2-5
Engine overheats . . . . . . . . . . . . . . . . . . . . .2-6
Engine runs, burner will not light . . . . . . . . . . .2-6
Engine runs roughly or stops . . . . . . . . . . . . . . .2-7
Engine will not start . . . . . . . . . . . . . . . . . .2-7
Low engine power or speed. . . . . . . . . . . . . . .2-7
Low water pressure. . . . . . . . . . . . . . . . . . .2-7
No heater fuel pressure . . . . . . . . . . . . . . . . .2-9
No water pressure . . . . . . . . . . . . . . . . . . . .2-10
No water temperature indication . . . . . . . . . . . .2-10
OPEN MAG VALVE indicator fluctuates . . . . . . .2-11
2-3. TROUBLESHOOTING TABLE.
Table 2-1. Direct Support Troubleshooting
MALFUNCTION
TEST OR INSPECTION
CORRECTIVE ACTION
1.
BURNER LIGHTS AND EXTINGUISHES WHENSTART BURNER SWITCH IS
RELEASED.
Step
Step
Step
1 .
Check for defective THERMOSTAT SELECTOR switch or thermo-
stats.
Test switch and thermostats (refer to page 2-62).
If switch is not defective, proceed to step 2.
2.
Check for loose or broken switch or thermostat wiring.
Repair or replace wiring (refer to page 2-61)
3. If thermostats, swiches and wiring are not defective, control
module must be replaced.
Replace control module (refer to page 2-74).
2-2
