skoda Workshop Repair Guides

Skoda Workshop Service and Repair Manuals

ABOUT US
Self-diagnosis of the Air Conditioning Unit III > < Self-diagnosis of the Air Conditioning II

Fabia Mk1

Fault table
   
Fault table
  Note
t  All the possible faults which can be detected by the air conditioning system control unit -J301- and can be displayed by -V.A.G 1552- or → Vehicle diagnosis, testing and information system VAS 5051 are listed below according to the fault code.
t  If faults only occur occasionally, these faults are displayed as “sporadic faults” (“SP”).
t  If components are indicated as faulty: First test all of the cables and plug connections to these components as well as the earth cables of the system according to the current flow diagram. Only if no fault is detected here should the part be replaced. This applies in particular for faults that are output as “sporadically occurred” (SP) faults.
t  After repair always erase the fault memory again using the vehicle system tester -V.A.G 1552 - or → Vehicle diagnosis, testing and information system VAS 5051 and interrogate again.
t  If in spite of a problem with the heating/air conditioning electronics no fault is detected, the function “03 - actuator diagnosis” → Chapter or “08 - read measured value block” → Chapter must be performed. If applicable problem-related fault finding without self-diagnosis must be performed.
t  If “Information in the literature” appears in the display of the vehicle system tester -V.A.G 1552- or → Vehicle diagnosis, testing and information system VAS 5051, look for the text required in the fault table by referring to the fault code.
Display -V.A.G 1552 -Possible cause of faultRectifying fault
00538
Reference voltage		Signal too great

Signal too small
t  Short circuit or open circuit on wiring or plug connections to air conditioning system control unit -J301-
–  Check wiring and plug connections to the air conditioning system control unit -J301- according to the current flow diagram.
 
t  The temperature flap control motor -V68- or the fresh/re-circulating air flap control motor -V154- is defective.
–  Analysing measured value block 004 and 005 → Chapter.
–  Performing final control diagnosis (function 03) → Chapter.
–  Successively remove plug connections on the temperature flap control motor -V68- and on the fresh/re-circulating air flap control motor -V154-, erase fault memory and interrogate again → Chapter. If the fault “reference voltage” is no longer detected, replace the corresponding control motor causing the fault once the connector is plugged in.
t  Air conditioning system control unit -J301- defective
–  If necessary replace air conditioning system control unit -J301- → Chapter and perform “Initiate basic setting” (function 04).
00576
Terminal 15		Signal too high
t  Voltage regulator on AC generator defective
–  Inspect AC generator → Current flow diagrams and Fitting locations
t  Wiring or plug connections to the air conditioning system control unit -J301- defective
–  Check wiring and plug connections to the air conditioning system control unit -J301- according to the current flow diagram.
Signal too low
t  Battery discharged
–  Check battery → Electrical System; Rep. Gr.27
t  AC generator defective
–  Inspect AC generator → Current flow diagrams and Fitting locations
t  Wiring or plug connections to the air conditioning system control unit -J301- defective
–  Check wiring and plug connections to the air conditioning system control unit -J301- according to the current flow diagram.
Open circuit/short-circuit to earth
t  Open circuit or short-circuit to earth on wiring or plug connections to air conditioning system control unit -J301-
–  Check wiring and plug connections to the air conditioning system control unit -J301- according to the current flow diagram.
00705
Relay for radiator fan 1st speed -J279 1)		Short circuit to positive
t  Short-circuit to positive on wiring or plug connections to the radiator fan control unit -J293-
–  Check wiring and plug connections to the radiator fan control unit -J293- according to the current flow diagram.
t  -J293- defective
–  -J293 - replace → Current flow diagrams and Fitting locations
Open circuit/short-circuit to earth
t  Open circuit or short-circuit to earth on wiring or plug connections to radiator fan control unit -J293-
–  Check wiring and plug connections to the radiator fan control unit -J293- according to the current flow diagram.
t  -J293- defective
–  -J293 - replace → Current flow diagrams and Fitting locations.
00706
Relay for radiator fan 2nd speed -J513 1)		Short circuit to positive
t  Short-circuit to positive on wiring or plug connections to the radiator fan control unit -J293-
t  -J293- defective
–  Check wiring and plug connections to the radiator fan control unit -J293- according to the current flow diagram.
–  -J293 - replace → Current flow diagrams and Fitting locations.
Open circuit/short-circuit to earth
t  Open circuit or short-circuit to earth on wiring or plug connections to radiator fan control unit -J293-
–  Check wiring and plug connections to the radiator fan control unit -J293- according to the current flow diagram.
t  -J293- defective
–  -J293 - replace → Current flow diagrams and Fitting locations.
00818
Evaporator vent temperature sender		Short circuit to earth
t  Short-circuit to earth on wiring or plug connections to the evaporator vent temperature sender -G263-
–  Check wiring and plug connections to the evaporator vent temperature sender -G263- according to the current flow diagram.
t  -G263- defective
–  Analysing measured value block 002 → Chapter
–  -G263- replace → Chapter
Open circuit/short circuit to positive
t  Open circuit or short-circuit to positive on wiring or plug connections to the evaporator vent temperature sender -G263-
–  Check wiring and plug connections to the evaporator vent temperature sender -G263- according to the current flow diagram.
t  -G263- defective
–  Analysing measured value block 002 → Chapter
–  -G263- replace → Chapter
00819
High pressure sender -G65		Short circuit to positive
t  Short-circuit to positive terminal or plug connections to the high pressure sender -G65-
–  Check wiring and plug connections to the high pressure sender -G65- in accordance with the current flow diagram
t  -G65- defective
–  Analysing measured value block 002 → Chapter
–  -G65- replace → Chapter
Open circuit/short-circuit to earth
t  Open circuit or short-circuit to earth on wiring or plug connections to high pressure sender -G65-
–  Check wiring and plug connections to the high pressure sender -G65- in accordance with the current flow diagram
t  -G65- defective
–  Analysing measured value block 002 → Chapter
–  -G65- replace → Chapter
Signal too great

Signal too small
t  Open circuit or short-circuit to earth or positive on wiring or plug connections between high pressure sender -G65- and air conditioning system control unit -J301-
–  Check wiring and plug connections to the high pressure sender -G65- in accordance with the current flow diagram
t  Faults in the refrigerant circuit (positive pressure or negative pressure)
–  Proceed with fault finding without self-diagnosis
t  -G65- defective
–  -G65- replace → Chapter
t  Compressor regulating valve, air conditioning system -N280- defective
–  Analysing measured value block 002 → Chapter
t  Air conditioning system control unit -J301- defective
–  If necessary replace the air conditioning system control unit -J301- → Chapter and perform initiate basic setting (function 04).
00898
Air conditioning compressor control		Short circuit to earth
t  Short-circuit to earth on wiring or plug connections to the compressor regulating valve, air conditioning system -N280 -
–  Check wiring and plug connections to the compressor regulating valve, air conditioning system -N280- according to the current flow diagram.
t  -N280- defective
–  Analysing measured value block 002 → Chapter
–  Performing final control diagnosis (function 03) → Chapter
–  Replacing compressor → Chapter
t  Air conditioning system control unit -J301- defective
–  If necessary replace the air conditioning system control unit -J301- → Chapter and perform initiate basic setting (function 04).
Open circuit/short circuit to positive
t  Short-circuit to positive on wiring or plug connections to the compressor regulating valve, air conditioning system -N280-
–  Check wiring and plug connections to the compressor regulating valve, air conditioning system -N280- according to the current flow diagram.
t  -N280- defective
–  Analysing measured value block 002 → Chapter
–  Performing final control diagnosis (function 03) → Chapter
–  Replacing compressor → Chapter
t  Air conditioning system control unit -J301- defective
–  If necessary replace the air conditioning system control unit -J301- → Chapter and perform initiate basic setting (function 04).
00926
Terminal 30		Signal too low
t  Battery discharged
–  Check battery → Electrical System; Rep. Gr.27
t  AC generator defective
–  Inspect AC generator → Current flow diagrams and Fitting locations
t  Wiring or plug connections to the air conditioning system control unit -J301- defective
–  Check wiring and plug connections to the air conditioning system control unit -J301- according to the current flow diagram.
Signal too high
t  Voltage regulator on AC generator defective
–  Inspect AC generator → Current flow diagrams and Fitting locations
t  Wiring or plug connections to the air conditioning system control unit -J301- defective
–  Check wiring and plug connections to the air conditioning system control unit -J301- according to the current flow diagram.
01087
Basic setting not performed		 
t  Basic setting (function 04) was not or incorrectly performed.
–  Perform initiate basic setting (function 04) → Chapter
01233
Coolant shut-off valve -N279 2)		Short circuit to positive
t  Short-circuit to positive terminal on wiring or plug connections to the coolant shut-off valve -N279-
–  Check wiring and plug connections to the coolant shut-off valve -N279- according to the current flow diagram
 
t  -N279- defective
–  -N279 - replace
Open circuit/short-circuit to earth
t  Open circuit or short-circuit to earth on wiring or plug connections to coolant shut-off valve -N279-
–  Check wiring and plug connections to the coolant shut-off valve -N279- according to the current flow diagram
 
t  -N279- defective
–  -N279 - replace
01271
Temp. flap control motor -V68		Short circuit to positive
t  Short-circuit to positive on wiring or plug connections to the control motor for temperature flap -V68-
–  Check wiring and plug connections to the control motor for temperature flap -V68- according to the current flow diagram.
t  control motor for temperature flap -V68- defective
–  Analysing measured value block 005 → Chapter
–  Performing final control diagnosis (function 03) → Chapter
–  Replace -V68- → Chapter and perform initiate basic setting (function 04) → Chapter
Short circuit to earth
t  Short-circuit to earth on wiring or plug connections to the control motor for temperature flap -V68-
–  Check wiring and plug connections to the control motor for temperature flap -V68- according to the current flow diagram.
t  control motor for temperature flap -V68- defective
–  Analysing measured value block 005 → Chapter
–  Performing final control diagnosis (function 03) → Chapter
–  Replace -V68- → Chapter and perform initiate basic setting (function 04) → Chapter
Blocked or dead

adaption limit exceeded

adaption limit not reached
t  Open circuit or short-circuit to earth or positive on wiring to the control motor for temperature flap -V68-
–  Check wiring and plug connections to the control motor for temperature flap -V68- according to the current flow diagram.
t  Temperature flap jams
–  Check smooth operation of temperature flap
t  control motor for temperature flap -V68- defective
–  Analysing measured value block 005 → Chapter
–  Performing final control diagnosis (function 03) → Chapter
–  Replace -V68- → Chapter and perform initiate basic setting (function 04) → Chapter
Adaption not performed
t  Basic setting (function 04) was not or incorrectly performed.
–  Perform initiate basic setting (function 04) → Chapter
01296
Vent temperature sender Centre -G191		Short circuit to earth
t  Short-circuit to earth on wiring or plug connections to the vent temperature sender, centre -G191-
–  Check wiring and plug connections to the -G191- according to the current flow diagram.
t  -G191- defective
–  Analysing measured value block 003 → Chapter
–  -G191- replace → Chapter
Open circuit/short circuit to positive
t  Open circuit or short-circuit to positive on wiring or plug connections to the vent temperature sender, centre -G191-
–  Check wiring and plug connections to the -G191- according to the current flow diagram.
t  -G191- defective
–  Analysing measured value block 003 → Chapter
–  -G191- replace → Chapter
01297
Vent temperature sender Footwell -G192		Short circuit to earth
t  Short-circuit to earth on wiring or plug connections to the vent temperature sender, footwell -G192-
–  Check wiring and plug connections to the -G192- according to the current flow diagram.
t  -G192- defective
–  Analysing measured value block 003 → Chapter
–  -G192- replace → Chapter
Open circuit/short circuit to positive
t  Open circuit or short-circuit to positive terminal on wiring or plug connections to the vent temperature sender, footwell -G192-
–  Check wiring and plug connections to the -G192- according to the current flow diagram.
t  -G192- defective
–  Analysing measured value block 003 → Chapter
–  -G192- replace → Chapter
01299
Data bus diagnostic interface Gateway -J533-3)		no communication
t  Fault in databus wiring
–  Check the data BUS wiring according to the current flow diagram.
t  Wrong or faulty vehicle voltage control unit -J519-
–  Read out Gateway fault memory → Electrical System; Rep. Gr.90
please read out fault memory 4)
t  Fault entry in Gateway
–  Read out Gateway fault memory → Electrical System; Rep. Gr.90
01314
Engine control unit		please read out fault memory 4)
t  Fault entry in 4AV control unit
–  Read out fault memory of the 4AV control unit → Engine, Fuel Injection; Rep. Gr.01
01317
Control unit with display in dash panel insert -J285		please read out fault memory 4)
t  Fault entry in the control unit with display in dash panel insert -J285-
–  Interrogate fault memory of dash panel insert → Electrical System; Rep. Gr.90
implausible signal
t  Fault in databus wiring
–  Check the data BUS wiring according to the current flow diagram.
t  Wrong or defective dash panel insert
–  Interrogate fault memory of dash panel insert → Electrical System; Rep. Gr.90
01596
Fresh/re-circulating air flap control motor -V154		Short circuit to positive
t  Short-circuit to positive terminal or plug connections to the -V154-
–  Check wiring and plug connections to the fresh/re-circulating air flap -V154- according to the current flow diagram.
t  -V154- defective
–  Analysing measured value block 004 → Chapter
–  Performing final control diagnosis (function 03) → Chapter
–  Replace -V154- → Chapter and perform initiate basic setting (function 04) → Chapter
Short circuit to earth
t  Short-circuit to earth terminal or plug connections to the -V154-
–  Check wiring and plug connections to the fresh/re-circulating air flap control motor -V154- according to the current flow diagram.
t  -V154- defective
–  Analysing measured value block 004 → Chapter
–  Performing final control diagnosis (function 03) → Chapter
–  Replace -V154- → Chapter and perform initiate basic setting → Chapter
Blocked or dead

adaption limit exceeded

adaption limit not reached
t  Open circuit or short-circuit to earth or positive on wiring or plug connections to the -V154-
–  Check wiring and plug connections to the fresh/re-circulating air flap control motor -V154- according to the current flow diagram.
t  Fresh/re-circulating air flap jams
–  Test smooth operation of fresh/re-circulating air flap
t  -V154- defective
–  Analysing measured value block 004 → Chapter
–  Performing final control diagnosis (function 03) → Chapter
–  Replace -V154- → Chapter and perform initiate basic setting (function 04) → Chapter
Adaption not performed
t  Basic setting (function 04) was not or incorrectly performed.
–  Perform initiate basic setting (function 04) → Chapter
65535
Control unit defective		 
t  Air conditioning system control unit -J301- defective
–  Replace the air conditioning system control unit -J301- → Chapter and perform initiate basic setting (function 04).

1) The radiator fan relay 1st speed -J279- and the radiator fan relay 2nd speed -J513- are integrated in the radiator fan control unit -J293-.
2) Only for vehicles with auxiliary heating.
3) The data bus diagnostic interface Gateway -J533- is integrated in the onboard supply control unit -J519-.
4) The fault is automatically erased once the data BUS signal is again faultless.
   

Self-diagnosis of the Air Conditioning Unit III > < Self-diagnosis of the Air Conditioning II