Diagnostic Functions
General:
The control module has a built-in diagnostic system, the Volvo on-board diagnostic (OBD) system, which continuously monitors itself and its input and output signals.
DTCs:
If the control module detects a fault it will store a diagnostic trouble code (DTC). The control module can store 21 diagnostic trouble codes (DTCs) for the S7O/V7O and 18 for the C/70. If for some reason a fault disappears after the diagnostic trouble code (DTC) has been permanently stored in the control module, information about the fault is stored in the control module.
Reading Off Volvo On-Board Diagnostic (OBD) System:
Fault data and other information can be read off using the Volvo Scan Tool (ST) connected to the data link connector (DLC) under the center console cover. The Volvo Scan Tool (ST) communicates with the engine control module (ECM) by a standardized interface.
Volvo On Board Diagnostic (OBD) System:
Using the Volvo Scan Tool (ST) it is possible to:
read off and erase diagnostic trouble codes (DTCs), counters and Frozen values.
read off (and erase) alarm causes.
activate components/functions according to predetermined patterns.
continuously monitor the value and status of input and output signals.
read off control module identification.
reading off and programming the lock and alarm system.
To activate the Volvo on-board diagnostic (OBD) system:
ignition on
battery voltage normal
Reading and Erasing Diagnostic Trouble Codes (DTCs):
The On-Board Diagnostic (OBD) system can identify 25 different faults in the form of diagnostic trouble codes (DTCs). Diagnostic trouble codes (DTCs) can only be erased when all stored diagnostic trouble codes (DTCs) have been read off at least once. This function can be used to read and erase stored diagnostic trouble codes (DTCs), counters and frozen values.
Reading Off and Erasing Alarm Cause:
The control module can store up to 9 different alarm causes, the same alarm cause can be stored several times. These alarm causes can be read off with the Volvo Scan Tool (ST).
NOTE: Alarm causes are erased at the same time as diagnostic trouble codes (DTCs).
Diagnostic trouble codes (DTCs) can only be erased when all stored diagnostic trouble codes (DTCs) have been read off at least once. For each diagnostic trouble code (DTC) frozen values for the following parameters can be read off:
The Alarm Causes That Can Be Stored Are:
Door open
Trunk lid/tailgate open
Hood open
Movement in the passenger compartment (ultrasonic sensor activated)
Broken window (glass breakage sensor activated)
Car tilted (tilt sensor activated)
Resistive wire broken
Ignition on (if the car has been hot-wired for example)
Fault in power supply (if battery leads have been cut or there is an open-circuit in the siren power supply)
Activating Components/Functions
Components and functions can be activated individually, but the ignition must be on.
The following components and functions can be activated:
Locking all central locking motors
Deadlocking
Unlocking side doors except driver's door
Unlocking driver's door on it own
Unlocking trunk lid/tailgate on its own
Opening fuel tank filler cover
Siren
Alarm horn
Indicator LED
Courtesy lighting
Starter relay
Turn signal lamp
Activating alarm
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:
Locking/unlocking signal from the driver's door lock switch
Locking/unlocking signal from the central locking switch
Locking/unlocking signal from the trunk lid/tailgate door lock switch
Trunk lid/tailgate unlocking signal from the internal switch
Fuel tank filler cover opening signal from the internal switch
Signal from door switches, side doors.
Signal from door switches, trunk lid/tailgate
Signal from hood switch
Signal from key in ignition switch
Airing signal, climate control
Signal from immobilizer
Courtesy lighting, on or off
Ultrasonic sensor, alarm signal
Glass breakage sensor, alarm signal
Siren, active/inactive
Tilt sensor, alarm signal
Resistive wire, alarm signal
Airing module, airing signal
Immobilizer, signal if immobilizer is OK
Indicator LED
Locking/unlocking signal to the central locking motors
Turn signal lamps
Starter relay
Reading Off Control Module Identification
The Volvo Scan Tool (ST) identifies control modules by reading a code from the memory of the module. This code contains the control module P/N and software version.
Reading Off And Programming Lock And Alarm Systems
This function can be used to read off programmed data and program data into the control module. Programming the lock and alarm functions adapts the system to market requirements and equipment levels. To program the system a PIN is required. There are 3 codes per car, one for each function.
Programming Remote Control
As standard two transmitters are programmed. One additional remote control can be programmed without reprogramming the first two transmitters. New remote control can be added by erasing old ones (if a remote control is broken or has been lost). The number of transmitters programmed can also be read off.
Programming Lock Type
Three lock types can be programmed - Standard, Deadlocking and Two-stage locking. The programmed lock type can also be read off.
NOTE: To program deadlocking, the car must have the correct lock unit.
Programming lock and alarm functions
Status: Alarm on/off
Indicates if this function is active - if the car has an alarm.
Status: Ultrasonic sensor on/off Indicates if the ultrasonic sensors are active.
Status: Glass breakage sensor on/off Indicates if the glass breakage sensor is active.
Status: Tilt sensor on/off
Indicates if the tilt sensor is active.
Status: Relocking on/off
Indicates if the automatic relocking function is active.
Status: Automatic activation on/off Indicates if the automatic activation function is active.
Status: Key activation on/off
Indicates if key activation of the alarm is active.
Status: Key deactivation on/off
Indicates if the key deactivation function is active.
Status: Central locking alarm on/off
Indicates if the central locking switch alarm activation function is active
Status: Panic alarm on/off
Indicates if the panic alarm function is active.
Status: Visual acknowledgment signal on arming/disarming on/off
Indicates if the locking/unlocking visual acknowledgment signal function is active.
Status: Automatic activation on/off
Indicates if the automatic activation function is active.
The programmed functions can also be read off.
Reading Off Programming Data
If the VGLA control module needs to be replaced, all data in the old control module must first be read off so that the new control module can be correctly configured. This is carried out with the Volvo Scan Tool (ST) as follows: Select PROGRAMMING and then READ PROG. STAT. The lock and alarm system configuration can now be read off. Read off and note all values. Replace control module according service and repair. Replacing main control module and program in the previously noted values. If the fault in the control module makes it impossible to read off the programmed values, use visual identification to determine how the lock and alarm system is equipped and programmed.
Identifying Alarm Components
Ultrasonic sensor
Ultrasonic sensors can be identified by two small microphones at the top of each B-post.
Movement sensor
Cabriolets and coupe s with an alarm system always have a movement sensor but no ultrasound or glass breakage sensor.
Glass breakage sensor
The glass breakage sensor is identified by removing the passenger side loudspeaker grille on the dashboard. If the car has a glass breakage sensor there is a small microphone located beside the loudspeaker.
Resistive wire
Resistive wires in the rear windows of 5-door models are identified by an additional wire in the rear windows (additional to the antenna strip).
Tilt sensor
The tilt sensor is located in the cargo compartment in the right wheel well and can be identified by folding up the carpet in 4-door models and removing the right-hand side panel in the cargo compartment. In 5-door models fold up the floor hatch and remove the cover over the wheel well for localize the tilt sensor.
Alarm horn/siren
The alarm is equipped with either an alarm horn or a siren. The alarm horn is located in the engine compartment on the firewall beside the upper engine mounting. If there is an alarm horn the car is not equipped with a siren. If there is no alarm horn the car has a siren.