Can-Bus Terminal Resistance, Checking: Notes
WARNING: This page does not describe the selected car, but rather 12 other vehicles, including the 2017 Audi S5, 2016 Audi S5, 2016 Audi S4, 2015 Audi S5, and 2015 Audi S4. However, it is still accessible from the selected car via links, so may be relevant.
- Models: A6, A7, A8 use Test Procedure A. Refer to TEST PROCEDURE A (A6, A7, A8) .
- Models A4 / S4, A5 / S5, Q5 use Test Procedure B. Refer to TEST PROCEDURE B (A4 / S4, A5 / S5, Q5) .
General Description
The Engine Control Module -J623- communicates with other CAN-Bus capable control modules.
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 -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 -J623-.
Special tools and workshop equipment required
- Multimeter.
- Wiring Diagram.
Test requirements
- Fuses OK.
- Battery voltage OK.
- Switch OFF all electrical and electronic accessories.
- Vehicles with Auto. Transmission, ensure Selector Lever position is in "P".
- Vehicles with Man. Transmission, ensure Shifter Lever position is in "N" with Parking Brake applied.
- Coolant Temperature: ≥ 80° C.
- Observe all safety precautions: SAFETY PRECAUTIONS .
- View clean working conditions: CLEAN WORKING CONDITIONS .
- For Hybrid vehicles refer to: HIGH VOLTAGE SYSTEM GENERAL WARNINGS .