Checking Communication Fault

Hint: For current information about the relevant circuit and signals, see the wiring diagram and signal specification for each system.

Data Link Connector (DLC)
- Check the power supply to the Data Link Connector (DLC) terminal #16. The voltage must be approximately battery voltage
- Check the cable for power ground and signal ground to the Data Link Connector (DLC) terminals #4 and #5.

Hint: When the VCT2000 is connected to the Data Link Connector (DLC) (is powered up) the indicator LED lights green. The indicator LED then flashes during communication with a control module. In the event of certain Internal faults, the VCT2000 indicator LED will be red!

Communication cables
- Check the communication cable between the Data Link Connector (DLC) terminal #7 and combined instrument panel terminal #B4 and with other connected control modules.
- Check for an open-circuit.
- Check for a short-circuit to ground.
- Check for a short-circuit to supply voltage.

CAUTION
If there is a fault in the communication cable, it will not be possible to establish communication on the high speed network. The first time there is communication on this cable, the high speed network cables are connected between the Data Link Connector (DLC) and the combined instrument panel to the high speed network in the car. This is controlled via a relay in the combined instrument panel.

- Check the communication cables between Data Link Connector (DLC) terminals #6 and #14 and combined instrument panel terminals #A19 and #A20. Check the cables for an open-circuit, short-circuit to ground and a short-circuit to supply voltage
- Also check the communication cables for the high speed network between the combined instrument panel and the other connected control modules

Communication cable for the cruise control as an independent system (not integrated)

- Check the communication cable between the Data Link Connector (DLC) terminal #13 and the cruise control control module.
- Check the cable for an open-circuit, short-circuit to ground and a short-circuit to supply voltage.

Communication cable for engine management system Fenix 5.2
- Check the communication cable between Data Link Connector (DLC) terminal #3 and the engine control module (ECM).
- Check the cable for an open-circuit, short-circuit to ground and a short-circuit to supply voltage

Control modules
- Check that the control module power supply and ground terminal are fault-free.


CAUTION
If none of the above checks help, try Reading the Diagnostic Trouble Codes (DTCs) in the combined instrument panel. This is carried out via VIDA vehicle communication.


VCT2000 and wiring
- Try new wiring and/or a new VCT2000 if no faults are detected after the above fault-tracing.