TT Roadster L4-2.0L Turbo (BPY) (2008)
Engine Control Module: Testing and Inspection
CAN-Bus terminal resistance, Selector Lever (E313) to Engine Control Module (ECM) (J623),
checking
CAN-Bus terminal resistance, Selector Lever (E313) to Engine Control Module (ECM) (J623), checking
Special tools, testers and auxiliary items required
‹› Multimeter.
‹› Wiring diagram.
Test requirement
‹› A CAN-Bus malfunction was recognized.
‹› The Engine Control Module (ECM) ( J623) fuses OK.
‹› The Selector Lever (E313) fuses OK.
‹› Battery voltage at least 12.5 volts.
‹› All electrical consumers such as, lights and rear window defroster, switched off.
‹› Vehicles with automatic transmission, shift selector lever into position " P" or "N".
‹› A/C switched off.
‹› Ground (GND) connections between engine/transmission/chassis OK.
‹› Ignition switched off.
Function
The Engine Control Module (ECM) (J623) communicates with the Selector Lever (E313).
The control modules are connected by two data bus wires which are twisted together (CAN_High and CAN_Low), and exchange information
(messages). Missing information on the CAN-bus is recognized as a malfunction by the Engine Control Module (ECM) (J623) and the other control
modules connected to the CAN-bus.
Trouble-free operation of the CAN-Bus requires that it have a terminal resistance. This central terminal resistance is located in the Engine Control
Module (ECM) (J623).
Test procedure
-
Perform a preliminary check to verify the customers complaint. Refer to => [ replacing ] See: Engine Control Module (ECM) (J623).
Start diagnosis
-
Remove the selector mechanism, far enough to gain access to the Selector Lever (E313) electrical harness connector - A -. Refer to 6 Spd. Direct
Shift Automatic Transmission 02E All Wheel Drive; Rep. Gr. 34.
-
Disconnect the Selector Lever (E313) electrical harness connector - A -.