Diagnostic Functions

Diagnostic functions

General




The control module has a built-in diagnostic system, Volvo Diagnostic, which continuously monitors internal functions as well as input and output signals. The control module stores any diagnostic trouble codes (DTCs). The diagnostic trouble codes (DTCs) can then be read using VIDA. Information is presented in VIDA in the same way as with other diagnostic systems.

Fault indication
If a fault arises in the tow hitch system the driver is warned via the driver information module (DIM) when the information lamp lights and an alert message is displayed.
A VIDA station must be connected to the data link connector (DLC) in order to identify the source of the fault.

Diagnostic trouble codes (DTCs)
A diagnostic trouble code (DTC) is stored if the control module detects a fault. The control module can store up to 8 diagnostic trouble codes (DTCs).
Diagnostic trouble codes (DTCs) for different types of short-circuit are only stored when there is no tow hitch connector connected to the socket. This is so that diagnostic trouble codes (DTCs) are not stored in the event of a fault in the trailer's cable harness or its connectors.
Should a fault disappear for any reason after being stored in the control module as a diagnostic trouble code (DTC), the information remains stored in the control module. If a fault is no longer permanent, the diagnostic trouble code (DTC) remains as intermittent.

Reading and erasing diagnostic trouble codes (DTCs)
Stored diagnostic trouble codes (DTCs) can be read off and erased using this function.
This function can also be used to read off whether the fault is still present (permanent) or whether it has now ceased (intermittent) after the diagnostic trouble code (DTC) has been stored.
Diagnostic trouble codes (DTCs) can only be erased once all the diagnostic trouble codes (DTCs) have been read off at least once.

Reading off the parameters
Data can be read off from the trailer module (TRM) using this function.

Battery voltage
Reads off the level of the power supply to the control module.

Input signal
Reads out the status of the stop lamp signal from the vehicle's right tail lamp.

Output signals
Reads out the status of the output signals to the cable harness for the tow hitch.

Tow hitch connector
Reads out whether the tow hitch connector is connected to the socket on the cable harness for the tow hitch.

Reading off control module identification
VIDA identifies control modules by reading off a number of codes from the control module memory. The codes contain information about the control module:
- hardware P/N (control module without software)
- hardware serial number (control module without software)
- software P/N
- software number, diagnostics.