Passat GLX V6 V6-2.8L (ATQ) (2001)
Vehicles with engine code ATQ (121-pin Engine Control Module -ECM-)
Function
The Engine Control Module (ECM) communicates with all databus-capable control modules via a CAN-Bus.
These CAN-Bus-capable control modules are connected via two CAN-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 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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V.A.G 1526 multimeter or V.A.G 1715 multimeter
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V.A.G 1594 Connector test set
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Wiring diagram
Test requirements
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DTC "P0600 Serial Communication Link" was detected by the Engine Control Module (ECM), Diagnostic mode 3: Check DTC memory. Refer
to "Scan Tool Testing/Diagnostic Mode 3: Check DTC Memory"
See: Testing and Inspection/Scan Tool Testing and Procedures/With Generic Scan Tool/Diagnostic Mode 3: Check DTC Memory
-
Ignition switched off.
Test sequence
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Connect test box to control module wiring harness, connect test box for wiring test. Refer to "Scan Tool Connecting/Test Box, Connecting For
Wiring Test".
See: Testing and Inspection/Reading and Clearing Diagnostic Trouble Codes/Scan Tool Connecting/With Generic Scan Tool/Test Box, Connecting For
Wiring Test
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Check the central termination resistor in the Engine Control Module (ECM):
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To do this, measure resistance between test box socket 58 + 60:
Specified value: 60 to 72 Ohms
If resistance value is not in expected range:
-
Replace Motronic Engine Control Module (ECM) -J220-.
If resistance value is in expected range:
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Disconnect test box from Engine Control Module (ECM).
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Connect test box to control module wiring harness.
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Check CAN-Bus wires for shorts among one another:
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To do this, perform a resistance measurement between test box sockets 58 + 60:
Specified value: Infinity Ohms
If specified value is obtained (wires have no shorts):
-
Eliminate malfunction in wires (see wiring diagram).
End Output (Function 06)
End Output
-
Press buttons -0- and -6-. This selects "End Output", function 06.
Indicated on display:
Rapid data transfer
Q
06 - End Output
-
Press -Q- button to confirm input.
Indicated on display:
Rapid data transfer
HELP
Enter address word XX