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Instrument Cluster / Carrier: Description and Operation






Combined instrument panel diagnostic functions

General




The control module has a built-in diagnostic system, the Volvo on-board diagnostic (OBD) system. This system continuously monitors itself and the input and output signals.

Diagnostic trouble codes (DTCs)
The control module will store a diagnostic trouble code (DTC) if it detects a fault. The control module can store a maximum of 25 diagnostic trouble codes (DTCs). The number of diagnostic trouble codes (DTCs) varies depending on the type of instrument. If a fault disappears for any reason after the diagnostic trouble code (DTC) has been permanently stored in the control module, information about the fault remains in the control module for a while. For each diagnostic trouble code (DTC) stored, a counter records the total number "fault-free" operating cycles since the diagnostic trouble code (DTC) was stored. If the control module does not register the fault after 10 completed operating cycles, the diagnostic trouble codes (DTCs) are erased automatically. They are "self-erasing".
An operating cycle is defined as where the ignition has been switched off and then on again and the vehicle has then reached a speed in excess of 30 km/h. The ignition must have been on (or the car driven) for longer than 5 minutes.

Reading off the Volvo on-board diagnostic (OBD) system
Fault data and other information can be read off using the VIDA PC which is connected to the data link connector (DLC) under the center console cover via VCT2000. The VIDA PC communicates with the control module via a standardized interface.

Volvo on-board diagnostic (OBD) system
With the VIDA PC it is possible to:
- read off and erase stored diagnostic trouble codes (DTCs)
- activate components or functions according to certain predetermined patterns
- continuously monitor the values and status of the input and output signals for the signals
- read off the control module identification
- program and read off the programmed values
- reset the mileage for a new car
- reset the service reminder lamp (SRL).
The following conditions must be met before the Volvo on-board diagnostic (OBD) system is activated:
- the ignition must be on
- the battery voltage must be normal.

Activating (testing) components and functions
This function allows the system components and functions to be activated individually. The ignition must be on for activation to be possible.

The following components and functions can be activated:
- temperature gauge (gas level gauge for bi-fuel cars)
- fuel gauge
- digital clock
- tachometer
- speedometer
- LCD test, general display
- LCD test in the clock
- LCD test in the odometer
- LCD test in the trip computer.
For further information about activation, see Description of component / function activation Description Of Component / Function Activation.

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.

The following parameters can be read off:
- speed, input signal
- engine speed (RPM), input signal
- engine coolant temperature (ECT), input signal
- outside temperature, input signal
- manipulated odometer
- fuel volume, calculated / attenuated
- gas volume, calculated / attenuated###ftnote### Applies only to Bi-fuel cars
- gas fuel finished###ftnote### Applies only to Bi-fuel cars
- status of the clock adjustment knob, input signal
- set button on trip computer, input signal###ftnote### Applies only to model years 1999 and 2000
- trip computer reset button, input signal
- trip computer mode selector, input signal
- trip odometer reset button, input signal
- high engine coolant temperature (ECT), warning lamp
- low fuel level, warning lamp
- outside temperature warning lamp
- mileage since service
- mileage to service
- engine hours since service
- time since service
- time remaining until service
- engine hours to service.
For further information about parameters, see Description of parameters Description Of Parameters.

Reading off the control module identification
The VIDA PC identifies control modules by reading a code from the memory of the module. This code contains information about the control module P/N and the present software version.

Programming and reading off the programmed values
With this option, the data in the control module can be programmed and read off. This programming adapts the system to the type of car, market requirements and the equipment level.
All these functions are dealt with via VIDA vehicle communication. Certain values are readable. Others are protectedby a PIN code.

Note! From model year 2000, the PIN code protected values, a new combined instrument panel and the trip computer function can only be programmed using the VIDA software manager.

The following can be programmed and read off:
- total mileage (km or miles)
- distance to service (km or miles)
- engine hours to service
- time remaining until service
- tire size
- fuel level calculation type in the fuel tank
- time display
- initial zeros
- speed warning
- flashing speed warning in the trip computer display###ftnote### Model year 2000
- the function for high temperature warning indication, diesel/Melco Economy###ftnote### Model year 2000-
- display for outside temperature
- unit for outside temperature
- trip computer function###ftnote### Protected by a PIN code
- calibration of the trip computer fuel consumption function###ftnote### Protected by a PIN code
- fuel level at which the fuel level warning lamp should be lit
- type of fuel level sensor###ftnote### Protected by a PIN code. Model year 2000
- engine system type for engine coolant temperature display###ftnote### Protected by a PIN code
- speedometer display###ftnote### Protected by a PIN code
- time delay###ftnote### Protected by a PIN code.

The following can only be read off:
- instrument function, outside temperature version or adaptation for a trip computer
- SRL function, activated or not
- speed warning function, activated or not
- input signal terminal #B12 function, activated or not
- 10 second lamp test function, activated or not
- programmed, factory or after market
- speed signal type function
- diesel high temperature warning function
- fuel tank volume
- PIN code, status
- type of speedometer.
For further information about parameters, see Description of programmed data Description Of Programmed Data.

Resetting the mileage, new car
Use this function to reset the mileage in the combined instrument panel for a new car. This allows the workshop to reset the mileage after all settings have been made. This is so that the customer receives a car with the mileage set to zero. This function can only be implemented once, and only then if the mileage is less than 500 km / 500 miles.

Resetting the service reminder lamp (SRL)
This option is used to reset the service reminder lamp (SRL) function.