Fault Code Table (Fault Codes, Flash Codes) - Webasto Thermo Pro 90 Series Service Installations

Thermo Pro 90
5.5

Fault code table (fault codes, flash codes)

Fault Fault
code code
(ana- (hexa-
logue) decimal)
F00 F01 No error
or F81
0* F91
F92
F2C
FA3
F07
FAC
F01 F02 No start
or F82
1* F4E
F32
F02 F03 Flame abort
or F83
2*
F03 F04 Supply voltage too high Power supply
or F84
3*
F04 F05 Flame was detected
or prior to combustion
4*
F06 F14 Temperature sensor
or F94 short circuit
6*
F07 F08 Fuel pump short circuit Wiring
or F88
7*
F08 F09 Combustion air fan
or F89 short circuit
8* F2D
*: Indicator lamp of control element flashing: Number of long flash pulses after 5 short flash pulses
Error message
Fuses
Electrical wiring
Heater lock-out
Control unit defective
Fuel system
Combustion air / exhaust
line
Burner unit
Fuel system
Burner unit
Exhaust gas temperature
sensor defective
Wiring
Coolant temperature sen-
sor defective
DP42 fuel pump defective
Wiring
Combustion air fan blocked Check operation of combustion air fan, replacing
Combustion air fan defec-
tive
5 Malfunctions and troubleshooting
Possible causes
Check fuses F1, F2 and F3
•
•
•
Delete heater lock-out
Replace control unit
Check fuel level
Check fuel filter
Checking tank extracting device and fuel line for
leaks
Bleed fuel system
Check combustion air/exhaust line for foreign
objects and clean if necessary
•
•
Check fuel level
Check fuel filter
Checking tank extracting device and fuel line for
leaks
Bleed fuel system
Clean burner unit or replace if necessary
Check battery
Check electrical connections
•
•
•
•
•
Check operation of coolant temperature sensor,
replacing if necessary
Check wiring for damage, break and short-circuit
Check operation of fuel pump, replacing if
necessary
Check wiring for damage, break and short-circuit
if necessary
Replace combustion air fan
Recommended action in workshop
Check battery connections:
+ at 12 / - at 9 / + at 3 (switch-on signal),
connector X8
Check control element
Check contacts of W-bus cable (yellow cable)
Clean burner unit or replace if necessary
Check glow plug
Check operation of exhaust gas temperature
sensor, replacing if necessary
Check prepressure in fuel system to fuel pump
Check delivery rate of fuel pump
Check wiring for damage
Check resistance
503