Rev. D 27-06-11
P/N 474131
41
Diagnostic LED's: SFS
NO
(HD )
NO
(Basic)
NO
Reset power to Heater and
retry. Heater should fire.
Does the Digital
Temperature Display show
Error Code “E05” or “E06”?
Heater starts and runs OK,
but temperature of exhaust
climbs to 204˚–260˚C in
3-5 minutes.
Heater starts after several
tries, exhaust temperature
stays below 121.1˚C.
OR
Heater doesn’t start at all
(exhaust stays cold).
Check pressure and volume
of fuel supply
Check the J3 and J6
connectors for corrosion/
looseness on the male
pins.
Check continuity in wiring
harness between Control
Board and Probe.
Continuity OK?
Disconnect the sensor and
check continuity across its
terminals. Resistance
should be 3.5-4.0 mega-
ohms.
= open circuit;
0 = shorted.
Does sensor check OK?
Clean/tighten pins as
needed.
Reset power to Heater
and retry. Heater should
fire.
NOT OK
NO
NO
NO
NO
NO
SFS "on"
Replace Stack Flue Sensor
Correct Fuel Supply, reset
Heater and retry. Heater
should fire correctly.
Repeat checks on fuel
supply, Thermal Regulator,
check for correct orifices,
etc.
DONE
DONE
YES
YES
YES
YES
NO
NO
YES
NO
OK
YES
Replace Heater
Control Board.
Replace Heater
Membrane Pad.
Reset power to Heater and
retry. Heater should fire.
Check Heat Exchanger Coil for
leaks, liming, soot, or low flow.
Correct problem;
Heater should fire.
Check Heat Exchanger
Coil for leaks, liming, soot,
or low flow.
Check Thermal
Regulator: Open at
48.9˚C?
Check Thermal-Regulator:
Seats correctly?
DONE
NO
DONE
Replace Heater Membrane Pad.
Replace Heater Control Board.
Reset power to Heater and
retry. Heater should fire.
Reset power to Heater and
retry. Heater should fire.
DONE
NO
YES
YES
DONE
NO
Section 5. Troubleshooting
