A4 Sedan V6-3.2L (BKH) (2007)
Control Module: Testing and Inspection
CAN-Bus Terminal Resistance, Transmission Control Module (TCM) J217 to Engine Control Module
(ECM) J623 , Checking
CAN-Bus Terminal Resistance, Transmission Control Module (TCM) J217 To Engine Control Module (ECM) J623, Checking
The Engine Control Module (ECM) J623 communicates with all databus capable control modules via a CAN databus.
These databus capable control modules are connected via two data bus wires which are twisted together (CAN_High and CAN_Low), and exchange
information (messages). Missing information on the databus is recognized as a malfunction and stored.
Trouble-free operation of the CAN-bus requires that it have a terminal resistance. The central terminal resistor is located in the Engine Control Module
(ECM) J623.
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.
-
Battery voltage at least 12.5 V.
-
Ignition switched off.
Procedure
-
Disconnect the Transmission Control Module (TCM) J217 electrical harness connector - direction of the arrow -.
NOTE: The Engine Control Module (ECM) J623 must remain connected for the following step.
-
Using a Multimeter, check the Transmission Control Module (TCM) J217 electrical harness connector terminals 2 to 6 for resistance.
Specified value: 60 to 72 Ohms (at approx. 20 degrees C)
If the specified value was not obtained:
-
Check the wiring connection for an open circuit, short circuit to Battery (+) or Ground (GND).
-
Check the wiring connection for damage, corrosion, lose or broken terminals.
-
If necessary, repair the faulty wiring connection.
If no malfunction is found in the wiring:
-
Replace the Engine Control Module (ECM) J623.
If the specified value was obtained:
Checking wiring
If the manufacturers test box is being used. Perform the following step.
-
Install the test box.
If the manufacturers test box is not being used. Perform the following step.
-
Remove the Engine Control Module (ECM) J623.
-
Using a Multimeter, check the Transmission Control Module (TCM) J217 electrical harness connector to the Engine Control Module (ECM) J623