A4 V6-3.0L (AVK) (2004)
Information Bus: Component Tests and General Diagnostics
With Generic Scan Tool
Terminal Resistance For CAN-Bus, Checking
The Engine Control Module (ECM) communicates with all data bus-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. This central terminal resistor is located in the Engine Control Module
(ECM).
Recommended special tools and equipment
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VAG1526A multimeter
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VAG1594A connector test kit
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VAG1598/31 test box
Test requirement:
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Ignition switched off.
Test sequence
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Connect test box to the Engine Control Module (ECM); wiring harness is not connected. See: Testing and Inspection/Reading and Clearing
Diagnostic Trouble Codes/Scan Tool Connecting/With Generic Scan Tool/Text Box, Connecting For Wiring Test
-
Check the central terminal resistor in the Engine Control Module (ECM):
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Connect multimeter between terminal 58 and 60 of test box for resistance measurement.
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Specified value: 60 ...72 Ohm
If the specification is exceeded or not met:
-
Replace Engine Control Module (ECM).