System Overview

Reading Off the Volvo On-Board Diagnostic (OBD) System
Overview





Fault information and other data can be read using VIDA connected to the data link connector (DLC) via VCT2000. The data link connector (DLC) is located on the left of the center console (the right of the center console for right hand drive cars). VCT2000 communicates with the DSA control module via a standardized interface.

Volvo on-board diagnostic (OBD) system
With VIDA it is possible to:
- Read off and erase stored diagnostic trouble codes (DTCs)
- Reset adaptations
- Activate components and functions according to certain predetermined patterns
- Continuously monitor the value and status of the input and output signals for the system
- Read off the control module identification.
To activate the Volvo on-board diagnostic (OBD) system for DSA:
- The ignition must be on
- The battery voltage must be normal.

Reading and erasing diagnostic trouble codes (DTCs)
Stored diagnostic trouble codes (DTCs) can be read off and erased using this function. The on-board diagnostic (OBD) system can identify 17 different faults in the form of diagnostic trouble codes (DTCs).

Note: Diagnostic trouble codes (DTCs) DSA-112, DSA-223, DSA-224 and DSA-233 are only stored in the DSA control module while the ignition is on / the engine is running. When the ignition is switched off, these diagnostic trouble codes (DTCs) are erased. Therefore the engine must be started before diagnostic trouble codes (DTCs) are read off from the control module. This is so that the control module is able to re-check and store diagnostic trouble codes (DTCs).

Diagnostic trouble codes (DTCs) can only be erased when all diagnostic trouble codes (DTCs) have been read at least once.

Note: After the diagnostic trouble codes (DTCs) are erased the DSA function is disengaged. The DSA function is re-engaged using the DSA switch. If no diagnostic trouble codes (DTCs) have been stored, the DSA warning lamp goes out after engagement.

Resetting the wheel adaptation
This function allows the DSA system wheel adaptations to be reset to their center positions.

Activating components and functions
This function allows the system components and functions to be activated individually. The following components can be activated:
- Torque limiting request
- DSA warning lamp, flash status.

Note: After Activation is completed, the DSA function is disconnected. The DSA function is re-engaged using the DSA switch. If no diagnostic trouble codes (DTCs) have been stored, the DSA warning lamp goes out after engagement.

For further information about Activating components / functions. [1][2]Initial Inspection and Diagnostic Overview

Reading off input and output signals
Using this function, the values and status of the control module input and output signals can be continuously read off.

Note: To obtain the relevant values, the engine must be running and the engine control module (ECM) must be initiated. The engine control module (ECM) is initiated the first time engine speed exceeds 600 rpm.

The following parameters can be read off:
- Engine speed (RPM), value
- Load signal, value
- Throttle position (TP) sensor, position
- Torque limiting, value
- Transmission type
- Control module initialization, status
- DSA function, status
- DSA switch, status
- DSA warning lamp, lit status
- DSA warning lamp, flash status
- Stop (brake) light switch, status
- The value for the left front wheel speed
- The value for the right front wheel speed
- The value for the left rear wheel speed
- The value for the right rear wheel speed
- Left front wheel adaptation, value
- Right front wheel adaptation, value
- Left rear wheel adaptation, value
- Right rear wheel adaptation, value
- Wheel adaptation permitted, status.
For further information about Reading off parameters. [1][2]Initial Inspection and Diagnostic Overview

Reading off the control module identification
VIDA identifies the control module by reading a code from the memory of the module. This code contains information about the control module P/N.