Skoda Octavia Workshop Manual page 26

01
Display Readout on V.A.G
block 1552
5 readout does not
vary
constant 255
constant 80
constant 0
6 do not analyse
8 less than 24
greater than 50
------------ ------------
Self-Diagnosis
Possible cause of fault
♦ Large quantity of unmetered air
♦ Spark plug faulty
♦ Fuel system pressure too low or too high
♦ Injector faulty
♦ Coolant temperature sender -G62 faulty
♦ Activated charcoal filter solenoid valve
-N80 faulty, blocked or sticking
♦ Lambda probe heater not operating
♦ Lambda probe faulty or dirty
♦ Short circuit to positive caused by:
Lambda probe or
Signal line or
Engine control unit
♦ Open circuit in wiring caused by:
Lambda probe or
Signal line or
Engine control unit
♦ Short circuit to earth caused by:
Lambda probe or
Signal line or
Engine control unit
♦ Basic setting of throttle valve control unit
not performed
♦ Throttle valve potentiometer in throttle valve
control unit -J338 faulty or incorrectly set
♦ Throttle cable incorrectly set
♦ Throttle flap sticking
♦ Throttle valve potentiometer in throttle valve
control unit -J338 faulty or incorrectly set
♦ Unmetered air between intake manifold
and air mass meter (results in fast idling)
Rectifying fault
- Eliminate cause of unmetered air
- Inspect spark plugs
- Test fuel pressure regulator and holding
pressure ⇒ page 24-44
- Test injectors ⇒ page 24-41
- Test coolant temperature sender -G62
⇒ page 24-31
- Test activated charcoal filter solenoid valve
⇒ page 01-12, Final control diagnosis
- Test lambda probe heater ⇒ page 24-13
- Interrogate fault memory ⇒ page 01-4, test
lambda probe if necessary ⇒ page 24-12
- Test lambda probe ⇒ page 24-12
- Test lambda probe ⇒ page 24-12
- Test lambda probe ⇒ page 24-12
- Carry out basic setting of throttle valve
control unit ⇒ page 24-10
- Test throttle valve control unit -J338
⇒ page 24-17
- Adjust throttle cable
⇒ Engine, Mechanical Components; Repair
Group 20
- Adjust throttle cable
⇒ Engine, Mechanical Components; Repair
Group 20
- Test throttle valve control unit -J338
⇒ page 24-17
- Rectify cause of unmetered air
OCTAVIA
Edition 11.98
S00.5109.51.20