Upper Electronic Module (UEM)
System Overview
Control module
The most important task of the upper electronic module is to manage the following functions:
- Siren
- Sun roof
- Movement sensor
- Rain sensor
- Interior roof lighting
- Cargo compartment lighting
- Sun visor lighting
- Remote control
- Automatic rear view mirror anti-dazzle
- Seat belt reminder.
The control module is integrated in the rear view mirror. If the control module is replaced, the rear view mirror assembly must also be replaced.
The upper electronic module communicates partly with components which are directly connected and partly with other control modules and components via serial communication and the Control area network (CAN).
The control module checks activations and input and output signals through an integrated diagnostic system. A diagnostic trouble code (DTC) is stored if the control module detects an error. In certain cases the upper electronic module replaces the faulty signal with a substitute signal.
Diagnostic trouble codes (DTC) are stored in the control module memory. The data can be read off using the VADIS/VIDA.
A simple way to check that the upper electronic module is supplied with power is to activate the seat belt reminder function Activate the seat belt reminder by sitting in the driver's seat. Switch on the ignition, do not fasten the seat belt. If the seat belt reminder lights, the upper electronic module is supplied with voltage. Another way of checking that the upper electronic module is supplied with voltage is to switch on the rear reading lamps.
Signals
The table below summarizes input and output signals to and from the upper electronic module. The signal types are divided into directly connected signals, serial communication and Control area network (CAN) communication. The illustration displays the same information and the Volvo part numbers.
Design
Siren
Data from the siren (Siren Control Module) to the upper electronic module contains configuration and status information. This data is carried via serial communication.
When the alarm is activated the siren sends continuous status signals to the upper electronic module.
The siren is equipped with a battery and a built-in battery charger so that it is independent of the vehicle power supply. The battery charger maintains battery voltage in the integrated battery. When the alarm is activated the power supply is monitored for the siren and serial communication between the siren and the upper electronic module. The siren sounds if the car's power supply to the siren is broken or if communication between the upper electronic module and the siren is interrupted. The battery and the battery charger in the siren cannot be changed separately. The entire siren must be replaced if it is faulty.
The siren is located in a protected position under the fender liner in the front right-hand wheel arch. The siren must be configured after replacement. Configuration is carried out using VADIS/VIDA.
The siren can be diagnosed.
Sun roof
The Sun Roof Module is operated by one switch. The switch is located in the same unit in the roof as the front reading lamps and the courtesy lighting. The sun roof can be opened, closed and tilted.
The sun roof is powered by a motor in the roof in front of the sun roof. The position of the sun roof is determined by two optical sensors.
There are diagnostics for the sun roof.
Movement sensor
The Mass Movement Sensor detects movement in the passenger compartment using radio waves at 2.450 GHz. The Doppler effect principle is used to determine if the frequency of the received microwave has been modified in comparison to the transmitted microwave. Any change in frequency is interpreted as a movement in the car. When movement is detected, a trigger signal is sent to the upper electronic module which activates the alarm.
The movement sensor is located in the headlining in the center of the car. This allows the sensor to cover as large an area as possible.
There are diagnostics for the movement sensor.
Rain sensor
The rain sensor module optically senses water on the windshield. An infra red beam of specific intensity lights a section of the windshield. The intensity of the reflected beam is measured and compared to the intensity of the transmitted beam. If there is water on the surface of the windshield, the beam distorts, reducing the intensity of the beam. If the beam is not reflected completely it is interpreted as rain on the windshield and the windshield wipers are started.
The signals from the upper electronic module are carried via serial communication. The rain sensor transmits the signals to the upper electronic module. These signals request a particular windshield wiper speed (depending on the amount of rain falling on the windshield), indicate that a sudden large splash has hit the windshield and register the light conditions outdoors.
The rain sensor is located in front of the rear view mirror on the inner side of the windshield. A special windshield is used on cars with rain sensors.
There are diagnostics for the rain sensor.
Interior roof lighting
There are a number of lamps inside the passenger compartment. The lamps include four reading lamps and a general courtesy lamp.
The front left and front right reading lamps and the courtesy light are located in the same unit in the roof, just above the rear view mirror. The two rear reading lamps are located in the roof above the rear seat.
The five lamps transmit control signals to the control module. These signals allow the control module to determine the status of the lamps and switches This allows faults such as broken bulbs, open circuits or jammed switches to be detected.
The five control signals are distributed as input signals at the four inputs in the upper electronic module. The control signal for the courtesy lighting shares the same inputs as control signals for the front reading lamps. The rear reading lamps each have their own input.
Two different lighting times can be programmed using VADIS/VIDA depending on the requirements of the customer.
- Short lighting time which is the time from when the door is unlocked or closed or from when the engine is switched off until the interior lighting goes out. The time can be set between 5 and 255 seconds. Normal setting is 30 seconds
- Long lighting time, which is the time from when a door is left open or from when a light is lit using a button to when the interior lighting goes out. The time can be set between 0 and 255 minutes. Normal setting is 10 minutes.
There are diagnostics for all lamps in the inner roof lighting.
Remote control
The remote control can be used to lock and unlock the doors, unlock the tailgate, to activate the approach lighting, and to activate the panic alarm (certain markets).
The receiver for the remote control is located in the rear view mirror and transmits signals to the upper electronic module. These signals determine:
- which function should be activated
- at which frequency the receiver receives the signal from the remote control
- which of the remote controls transmitted the signal
- the signal strength received from the remote control.
Up to six remote controls can be stored in the upper electronic module. The control module stores the identity and PIN for each remote control.
The remote control identity and PIN are also stored in the central Volvo database When replacing the upper electronic module, this data is transmitted to the car. This means that the remote controls do not need to be replaced and can be used with the new upper electronic module.
There are two different types of remote control, depending on whether the car is a late or an early model. The two variants are programmed into the control module in different ways. The early variant has an 8 digit PIN. The late variant has one 8 digit and one 16 digit PIN.
The early version and late version differ by chassis number.
Information regarding at which production plant a car was manufactured can be found in the VIN number. The 7th character from the right in the VIN indicates the production plant.
If the seat and power door mirrors in the car have a memory function, these functions are affected by the remote controls which are stored in positions 1, 2 or 3. The memory functions store the seat and power door mirror settings at the time the car was locked using one of these remote controls. Next time the car is unlocked using the same remote control, the seat and the power door mirrors move to the same settings.
The remote control battery can be replaced.
Rear view mirror
The rear view mirror has an automatic anti-dazzle function for when light from behind the car is too bright in the mirror (option in certain markets).
One photo sensor on the front of the rear view mirror, and one on the rear side compare light intensity. When the intensities differ by a specified amount the anti-dazzle function compensates to the required degree. The upper electronic module receives and manages the signals from the two photo sensors.
The anti-dazzle function can be set to the customer requirements. The selectable values are Light, Normal and Dark. Initial setting is Normal.
LEDs for the seat belt reminder are located in the rear view mirror, above the mirror lens.
CAUTION: The rear view mirror with automatic anti-dazzle can only be installed in the factory. Upgrading to, or removing an anti-dazzle rear view mirror cannot be carried out after market due to software limitations.
There are diagnostics for the functions in the rear view mirror.
Function
Sunroof operation
The sun roof communicates with the upper electronic module (4/70) via serial communication. The sun roof has an internal control module (4/33) which manages this communication.
Data about the sun roof position and data used for diagnostics is sent from the sun roof to the upper electronic module. Data about the position is sent on to other control modules, including the climate control module via the central electronic module (4/56).
The communication between the upper electronic module and the sun roof consists of diagnostic information.
Rain sensor
The rain sensor (7/149) determines that there is water on the windshield. The sensor assesses the volume of water on the windshield and the prevailing exterior light conditions. This data is then sent, via the upper electronic module (4/70), to other control modules in the car on the Control area network (CAN). These control modules in turn ensure that the windshield wipers are set to the correct speed. The rain sensor senses if the windshield is dirty or covered with traffic film and automatically compensates accordingly. The rain sensor also senses heavier splashes on the windshield. The windshield wipers are then operated at top speed.
The rain sensor communicates with the upper electronic module via serial communication. The power supply is from the upper electronic module via the power supply signal EXT.X, when the ignition key is in positions I or II. The rain sensor is active for 10 minutes after the ignition has been switched off.
The steering wheel module (3/130) sends signals via the control area network (CAN) to the central electronic module (4/56) and upper electronic module about the position of the wiper stalk. If the stalk is moved to the intermittent wiping/rain sensor position, the upper electronic module transmits this data to the rain sensor which is then activated.
The rain sensor transmits data via the upper electronic module to the central electronic module, which then controls the wiper motor. The sensitivity can be adjusted using the collar on the wiper stalk.
The upper electronic module transmits a fault message to the central electronic module if there is a fault in the rain sensor. If there is a fault message when the rain sensor is active, the central electronic module selects top speed for the windshield wipers until the windshield wiper stalk is moved from the intermittent/rain sensor position. If the fault recurs, intermittent wiping will be activated when the wiper stalk is next moved to the intermittent/rain sensor position, although at a fixed interval.
Interior roof lighting
The interior roof lighting and reading lamps, front (3/117) and rear (10/150), five lamps in total, are controlled via the upper electronic module (4/70) in that they are supplied with voltage directly from the control module when each switch is activated. The courtesy lighting is also activated when the doors are opened or when local lighting is activated.
Data is sent to the upper electronic module from the central electronic module (4/56) via the Control area network (CAN). This data indicates which doors or tailgate/trunk lid are opened or closed.
The request for keyhole lighting, courtesy lighting and cargo compartment lighting is sent from the upper electronic module to the central electronic module (4/56) and rear electrical module (4/58) via the Control area network (CAN).
Cargo compartment lighting (10/25) is also supplied with voltage by the upper electronic module. The lamp is activated when the central electronic module indicates to the upper electronic module that the tailgate is open.
Sun visor lighting (10/114-115) is supplied with voltage by the upper electronic module using the voltage supply signal EXT.X. The lamp is activated when the flap covering the mirror in the sun visor is opened.
Automatic rear view mirror anti-dazzle
The upper electronic module receives data from two photo sensors, one on the front and one on the reverse of the rear view mirror. If the upper electronic module determines that the anti-dazzle function is required, a signal is sent to the electro-chromatic mirror which diffuses to the level required.
The signal transfer occurs internally in the rear view mirror, and is carried out directly between the upper electronic module and the anti-dazzle function.
CAUTION: The rear view mirror with automatic anti-dazzle can only be installed in the factory. Upgrading to, or removing an anti-dazzle rear view mirror cannot be carried out after market due to software limitations.
Seat belt reminder
The seat belt reminder is activated when the upper electronic module (4/70) receives a signal from the central electronic module (4/56), via the Control area network (CAN), which indicates that the seat belt is not engaged despite someone sitting in the front seat. Data is also transmitted to the driver information module (5/1) which indicates to the driver that the seat belt is not being used in one of the front seats.
General
The upper electronic module (UEM) has a built-in diagnostic system, the Volvo on-board diagnostic (OBD) system, which 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 up to 5 diagnostic trouble codes (DTCs). 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.
Reading and erasing diagnostic trouble codes (DTCs)
Stored diagnostic trouble codes (DTCs) can be read off and erased using this function.
Diagnostic trouble codes (DTCs) can only be erased when all diagnostic trouble codes (DTCs) have been read at least once.
NOTE: Certain functions cannot be carried out before diagnostic trouble codes (DTCs) have been erased.
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 number of remote controls
- The number of the remote control
NOTE: One of the remote control buttons must be activated when reading off.
- The activated buttons on the remote control
NOTE: One of the remote control buttons must be activated when reading off.
- Voltage to the mass movement sensor, status
NOTE: Listed as On or Off. The mass movement sensor is supplied with voltage (On) when the alarm is activated and the sensors are connected.
- Alarm status
NOTE: Indicates the alarm setting and alarm sensor setting. Six states can occur:
Alarm status 1: Not activated and not deployed, connected sensors.
Alarm status 2: Activated and not deployed, connected sensors.
Alarm status 3: Activated and not deployed, disconnected sensors.
Alarm status 4: Activated and deployed, connected sensors.
Alarm status 5: Activated and deployed, disconnected sensors.
Alarm status 6: Not activated and not deployed, disconnected sensors.
- Front left reading lamp, status
- The switch for the front left reading lamp
- Front right reading lamp, status
- Switch for the front right reading lamp
- Rear left reading lamp, status
- The switch for the rear left reading lamp
- Rear right reading lamp, status
- The switch for the rear right reading lamp
- The switch for the general lighting
- Extended X-supply, status
NOTE: X-supply supplies power to the sunroof, mirror lamps and rain sensor. X-supply is active when the Controller area network (CAN) is active, and for a short time after the Controller area network (CAN) is no longer active. This time varies and depends on a number of parameters.
- Local lighting, status
- Cargo compartment lighting, status
- The degree of anti-dazzle for the rear view mirror
NOTE: The parameter can only be read off when the engine is running and back-up (reverse) gear is not selected.
100% means that the rear view mirror is fully dimmed.
0% means that the rear view mirror is not dimmed.
- Supply voltage, sun roof
NOTE: The following parameters for the sun roof are read off from a separate vehicle communication input for the upper electronic module (UEM).
- Button activation, forward
- Button activation, backward
- Button activation, tilt
- Button activation, auto
- Motor, forward
- Motor, backward.
Activating components and functions
NOTE: A short delay can occur before a component is activated.
Remote control activations can only be carried out if the key is not in the ignition. Lock activations can only be carried out if the doors are shut.
With this function the components and functions associated with the upper electronic module (UEM) can be activated.
The following components/parameters can be activated in alternative ways:
- General lighting, directly to the lamp
- Front left reading lamp, directly to the lamp
- Front right reading lamp, directly to the lamp
- Rear left reading lamp, directly to the lamp
- Rear right reading lamp, directly to the lamp
- Extended X-supply
- Voltage to mass movement sensor
- Seat belt reminder
- Remote control, activate the button
- Local lighting
- Cargo compartment lighting
NOTE: The following activations for the sun roof can be made from a separate vehicle communication input for the upper electronic module (UEM).
- Button activation, forward
- Button activation, backward
- Motor, forward
- Motor, backward.
Reading off and programming data
With this option it is possible to read programmed data and program in data.
NOTE: If possible, read off all data from the control module before replacing the control module. After replacement, the current data must be programmed into the new control module. The following customer parameters must be read off before the control module is replaced. This is so that the same information can be programmed in to the new control module.
With auto mode:
The general lighting lights and remains lit for 30 seconds when:
The door has been unlocked from outside using a key or the remote control.
The engine has been stopped and the ignition key turned to position 0.
The default period is 30 seconds. This can be changed to between 5 and 255 seconds.
The general lighting lights and remains lit for 10 minutes when:
One of the doors is opened after unlocking.
When the lamp is lit using a button.
The default period can be reprogrammed from 0 to 255 minutes at 10 minute intervals.
The strength of the interior rear view mirror anti-dazzle. There are three positions; a normal position, one with stronger anti-dazzle and one with weaker anti-dazzle.
Reading off the control module identification
VADIS/VIDA identifies the control modules by reading off a number of codes from the control module memory.
The codes contain information about the control module's:
- hardware P/N (control modules without software)
- hardware serial number (control modules without software)
- software P/N
- P/N diagnostic software.
Programming remote controls
Add remote control
This function is used when the customer wishes to order extra remote controls in addition to those supplied on delivery. The PIN-code for a new remote control must be programmed into the control module memory before the remote control can be used.
The control module memory has room for six remote controls.
Removing remote controls
This function is used when the customer wishes to erase one or more remote controls from the control module memory, so that the remote control cannot be used any longer. All the available remote controls should be at hand when the erasing is being carried out.
Downloading software and replacing the control module
New software can be downloaded into the upper electrical module. When ordering software, the hardware and the software in the car is compared to the Volvo central database. If the comparison is OK the software is downloaded to the control module. The PINs for the existing remote controls are downloaded at the same time.
If the comparison between the car and Volvo central database is not OK, the database is updated with the relevant configuration. When this is complete the software and PINs are downloaded.
When installing a completely new upper electronic module in the car the PINs for the existing remote controls are downloaded to the control module. New remote controls do not need to be ordered after a software download or after the control module is replaced.
The control module is integrated in the rear view mirror. If the control module is replaced, the rear view mirror assembly must also be replaced.
The upper electronic module must be unlocked using a unique PIN to download software or to add remote controls to the upper electronic module. VADIS/VIDA carries out the unlocking automatically. The PIN is obtained from the Volvo central database and is sent with the software package when ordered, when remote controls are to be added or erased, or when a new upper electronic module is installed in the car and loaded with software.
Because of the unique PIN, the upper electronic modules cannot be moved between cars.
Three customer parameters can be programmed into the upper electronic module. These customer parameters are stored in the control module but not in the Volvo central database. This means that the customer parameters must be reprogrammed when the hardware is replaced.
Two different times for internal lighting can be programmed depending on the requirements of the customer. These times are parameters that are adjusted directly using the diagnostic tool:
- Short lighting time which is the time from when the door is unlocked or closed or from when the engine is switched off until the interior lighting goes out. The time can be set between 5 and 255 seconds. Normal setting is 30 seconds
- Long lighting time, which is the time from when a door is left open or from when a light is lit using a button to when the interior lighting goes out. The time can be set between 0 and 255 minutes. Normal setting is 10 minutes.
In addition the degree of anti-dazzle of rear view mirrors with automatic anti-dazzle function can be set to the customer requirements. The selectable values are Light, Normal and Dark. This programming is carried out by ordering and carrying out software downloads, especially for setting anti-dazzle.