Skoda OCTAVIA MK1 Service Manual page 262

Connect and lock the test box
–
-V.A.G 1598/18 --1- to wiring loom of the
gearbox control unit -1--2-.
Check CAN databus cables with the
–
terminating resistance in the engine and
ABS control unit:
Measure resistance between test box
–
sockets 3 and 25.
For vehicles ► 04.99
Specified value: 115...135 Ω.
For vehicles 05.99 ►
Specified value: 55...75 Ω.
If the measured value does not correspond
to the specified value:
Perform the test according to the
–
following table:
Display
0...5 Ω
t Short-circuit between databus lines
135...∞ Ω or
t
72...∞ Ω
t
t
If the measured value corresponds to the specified value:
– Fit again plug at the gearbox control unit.
– Switch on ignition.
– Erase all faults from the fault memory and conduct a test drive.
Once again read out the fault memories of all control units using the "automatic test
–
sequence".
If a fault is still shown on the data bus system in the engine control unit after the test drive.
Check voltage supply of the gearbox control unit
–
locations.
– Check the CAN databus cables for a short circuit to positive and/or to earth
If the wires are not found to be faulty and if the voltage supply is OK:
– Replace gearbox control unit:
Continuing test if there is a fault on the data bus system:
Cause
Line interruption
Short circuit to positive
Transition impedances
→ Automatic gearbox → Rep.
→ Current flow diagrams and Fitting
Gr.01.
262
Solution
Check wiring → Anchor
Check wiring → Anchor
→ Anchor.