Skoda OCTAVIA MK1 Service Manual page 146

5°km/h.
Readout on Possible cause of fault
-V.A.G 1552-
00635
Lambda probe
heating
upstream of
catalytic
converter
defective
t
t
t Lambda probe defective
t
Note
t Regarding fault code 00635:
t The positive voltage supply for the lambda probe heating occurs via the fuel pump relay.
The earth distribution for the lambda probe heating is performed by the engine control unit,
t
i.e the total filament current for the lambda probe heating flows via the engine control unit.
Readout on Possible cause of fault
-V.A.G 1552-
For vehicles
08.97 ►
00650
Line interruption or short-
circuit to positive and/or
earth between engine
control unit and lambda
probe
Power output stage in the
engine control unit defective
(engine control unit
defective).
Fuel pump relay/actuation of
fuel pump relay defective
Possible Rectifying fault
effects
irregular
t –
idling
possible
t exhaust
–
problems
–
–
–
Possible effects
146
Checking lambda control
→ Chapter.
Remove open circuit in wiring
or short circuit according to
current flow diagram
→ Current flow diagrams and
Fitting locations.
Replacing engine control unit
→ Chapter.
Replace lambda probe.
Test fuel pump relay and
control → Chapter.
Rectifying fault