After analysing the information the automatic gearbox control unit distinguishes between sporadic and static
(permanent) faults => Fault table, from page
and stores these.
If faults do not reoccur within
min. 5 km (3 miles) or 6 minutes
max. 20 km (12 miles) or 24 minutes,
they are stored as sporadic faults.
Electrical faults that affect vehicle performance can be determined with the fault reader V.A.G 1551.
The possibilities offered by self-diagnosis can only be fully exploited with operating mode 1 "Rapid data transfer"
of fault reader V.A.G 1551.
Functions which the fault reader V.A.G 1551 can register => page
, List of selectable functions.
Safety functions of gearbox control unit
If critical faults occur when driving, the gearbox will continue to operate in an emergency running mode. If the
fault occurs in "D", "3" or "2", then 3rd gear emergency mode is activated.
If the fault occurs in "1","P", "N" or "R" then the emergency running mode for that stage is activated.
If the engine is started again in the emergency running mode and the fault occurs when selector lever is in
position "D", "3" or "2" then 3rd gear is activated hydraulically, until the fault is rectified.
For faults which can lead to emergency running:
The gearbox will remain in emergency running mode; until the fault is no longer recognized by the control unit
over a predetermined period.
Faults which may lead to emergency running:
Open circuit in wiring, short-circuit, electrical or hydraulic components defective.
Wiring open circuit and/or data Bus wiring short circuit.
Gearbox control unit fault recognition
If a fault exists it is stored as a static fault. If the fault no longer exists after a predetermined period or distance
travelled, it is considered a sporadic fault.
Faults which are stored in the memory as sporadically occurring faults, will be displayed as "sporadic faults"
when retrieved by fault reader V.A.G 1551. "SP" appears on the right of the display in such cases. If the printer
is switched on, "sporadic faults" are printed out after the fault is addressed.
Faults which are stored in the memory as sporadically occurring faults are automatically erased after 1,000 km
(625 miles) or 20 hours.
Inoperative Data bus signals will be detected by the control unit on vehicles equipped with Data bus. Defective
Data bus wiring e.g. open circuits can be directly detected. Conclusions cannot be drawn as to where the Data
bus wiring is defective, until all control unit fault memories have been interrogated.
Fault reader V.A.G 1551
◆ The display group numbers will be 3 digits from July 1996 (up-to-date V.A.G 1551 programme card).
◆ From July 1997 a further number on the right next to the fault code will be displayed/printed-out when
interrogating the fault memory (up-to-date programme card version of V.A.G 1551). This number indicates
the type of fault, which is also given again in words under the affected component.
Golf 1998 ➤
Automatic gearbox 01M self-diagnosis - Edition 10.1997
2
01 - Self-diagnosis, Electrical check
