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

Reading off the Volvo on-board diagnostic (OBD) system

General
Fault data and other information can be read off using the VIDA PC connected to the data link connector (DLC) via the VST 2000. The VIDA PC communicates with the control module via a standardized interface.
The data link connector (DLC) is located in the passenger compartment.
To activate communication with the seat control module the following conditions must be met:
- Battery voltage must be above approximately 11 V
The ignition can be switched off.

Reading and erasing diagnostic trouble codes (DTCs)
This function allows stored diagnostic trouble codes (DTCs), counters and frozen values to be read off and erased.
Diagnostic trouble codes (DTCs) can only be erased after all diagnostic trouble codes (DTCs) have been read off at least once and the cause of the fault has been remedied.
When the engine control module (ECM) detects a fault, the values of certain parameters are frozen. These can be read off with the diagnostic trouble code (DTC).
Frozen values for the following parameters can be read off:
- The motors' position and speed (via potentiometers)
- The position of the buttons on the control panel
- Motors activated (forward/backwards) or not
- Supply voltage to control module

Reading off input and output signals
This function allows the value of all the control module inputs and outputs to be read off:
- Supply voltage
- Control module relays (outputs to motors)
- Potentiometers' values
- Motors' speed
- Control panel buttons

Read off control module identification
The control module can be identified by reading off a code from the control module memory. This code contains the control module P/N and software version.