BATTERY VOLTAGE Volvo XC90 I facelift

BATTERY VOLTAGE

The task of the rear electronic module (REM) is to check the voltage of the battery. The value of the voltage is transmitted out on the CAN network as a reference for other control modules.

The Central electronic module (CEM) receives this signal and checks it against its own supply voltage from the battery. The value is used when diagnosing the charging function.

Scheme 243

The fuel level in the gasoline tank is measured by the fuel level sensor (7/143). The level in the gas tank is measured by the fuel level sensor (7/156) (CNG) or (7/153) (LPG). The signals from the sensors are transmitted to the rear electronic module (REM) (4/58).

The rear electronic module (REM) calculates the quantity of fuel remaining in each tank and transmits this information via the controller area network (CAN) to the driver information module (5/1) and engine control module (ECM) (4/46). The driver information module (DIM) also receives data via the controller area network (CAN) from the engine control module (ECM) (4/46) indicating which type of fuel the car is running on. The gas level in the tank is displayed via the fuel gauge. The gasoline fuel level is displayed in the text window in the driver information module (DIM).

Scheme 244

The rear electronic module (REM) (4/58) controls the shut-off valves, (8/88-90) (CNG) and (8/76) (LPG), via a relay (which supplies the valves with power when they should be open.

The rear electronic module (REM) receives information via the controller area network (CAN) from the engine control module (ECM) (4/46) indicating that the car should run on LPG or CNG. The rear electronic module (REM) also receives information via the controller area network (CAN) from the central electronic module (CEM) (4/56) indicating the position of the ignition and data about collision status. When the ignition is on and no collision has been registered, the rear electronic module (REM) activates the relay, which supplies the valves with power.

The rear electronic module (REM) deactivates the relay in the following cases

1. there is a signal from the engine control module (ECM) indicating that gasoline operation has been selected
2. ignition off
3. the collision status changes
4. there is a fault in the communication on the controller area network (CAN).

The relay can be activated via a diagnostic command, for example, to allow the tank to be drained. Activation is carried out in VIDA via the vehicle communication socket.

Scheme 245

The rear fog lamps (10/46, 10/53) are activated by pressing the button for the rear fog lamps in the lamp switch module (3/111). The light switch module (LSM) transmits a request to light the lamps to the central electronic module (CEM) (4/56) using serial communication. The central electronic module (CEM) transmits the request to the rear electronic module (REM) (4/58) via the Controller area network (CAN).

Central Electronic Module (CEM) transmits information

1. back to the light switch module (LSM) to light the LED in the button
2. via the Controller area network (CAN) to the driver information module (DIM) (5/1) to light the indicator lamp for the rear fog lamps.

The rear electronic module (REM) sends the status of the lamp fault via the Control area network (CAN) to the central electronic module (CEM). In the event of a fault, the central electronic module (CEM) transmits data via the Control area network (CAN) to the driver information module (DIM) which displays a text message.

Scheme 246

The parking lamps (10/17-18) and license plate lighting (10/3) light when

1. the knob in the light switch module (LSM) (3/111) is in the low beam position
2. the knob in the light switch module (LSM) is in the parking lamp position
3. low beam is lit via the low beam automatic function.

The lamp switch module (LSM) transmits data using serial communication to the central electronic module (CEM) (4/56) to activate the lamps.

The central electronic module (CEM) transmits the data via the controller area network (CAN) to the rear electronic module (REM) which activates the lamps.

The rear parking lamps and license plate lighting are powered via the rear electronic module (REM) (4/58).

In the event of a bulb fault for the rear parking lamps or license plate lighting, data is transmitted on the controller area network (CAN) from the rear electronic module (REM) to the driver information module (DIM) (5/1) and a text message is displayed.

There is a Limp Home function for the parking lamps so that they will work even if there is a fault in the controller area network (CAN) or in the serial communication between the light switch module (LSM) and the central electronic module (CEM).

Scheme 247

Manual transmissions

The back-up (reversing) lamps (10/48, 10/55) are activated when back-up (reverse) gear is selected. The switch (3/10) on the transmission is then closed. A directly connected signal is transmitted to the central electronic module (CEM) (4/56) indicating that back-up (reverse) gear is selected. The central electronic module (CEM) transmits the information via the controller area network (CAN) to the rear electronic module (REM) (4/58) to activate the back-up lamps. The rear electronic module (REM) activates the relay and the back-up lamps are supplied with power via the relay.

Automatic transmission

The back-up (reversing) lamps (10/48, 10/55) are activated when back-up (reverse) gear is selected. The transmission control module (TCM) (4/28) transmits information via the Control area network (CAN) to the central electronic module (CEM) (4/56) indicating that back-up (reverse) gear is selected. The central electronic module (CEM) transmits the information via the controller area network (CAN) to the rear electronic module (REM) (4/58) to activate the back-up lamps. The rear electronic module (REM) activates the relay and the back-up lamps are supplied with power via the relay.

Scheme 248

The stop lamps (10/43, 10/50) are activated when the brake switch is (3/9) closed. A directly connected signal is transmitted via the central electronic module (CEM) (4/56) to the rear electronic module (REM) (4/58) and activates the relay. The lamps are powered via the relay. The central electronic module (CEM) transmits the data via the Controller area network (CAN) to the rear electronic module (REM) indicating that the stop lamp switch is activated. The rear electronic module (REM) sends status information for the lamp fault via the Control area network (CAN) to the central electronic module (CEM). In the event of a fault, the central electronic module (CEM) transmits data via the Control area network (CAN) to the driver information module (DIM) (5/1) which displays a text message.

Scheme 249

When the stop lamp switch (3/9) is closed, a signal is transmitted to the central electronic module (CEM) (4/56). The signal is transmitted from the central electronic module (CEM) to the rear electronic module (REM) (4/58) via a directly connected cable. The high mounted stop lamp is supplied with power directly from the rear electronic module (REM). The stop lamp is supplied with power for as long as the stop lamp switch is closed.

Scheme 250

Rear demist (9/2) is activated by pressing the switch on the climate control module (CCM) (3/112). The climate control module (CCM) transmits the data via the Control area network (CAN) to the central electronic module (CEM) (4/56). The central electronic module (CEM) checks that the conditions to start the demist have been met. If the conditions are met, a request is transmitted via the controller area network (CAN) to the rear electronic module (REM) (4/58) to activate the relay. The rear electronic module (REM) powers the relay and the demister is powered.

The central electronic module (CEM) also transmits a request via the Control area network (CAN) back to the climate control module (CCM) to light the LED in the switch.

Scheme 251

The cargo compartment lighting is activated when the trunk lid is opened. The central electronic module (CEM) (4/56) receives a signal from the lock (3/78) in the trunk lid. The central electronic module (CEM) transmits the information via the Controller area network (CAN) to the rear electronic module (REM) (4/58) about the status of the trunk lid. A request for cargo compartment lighting is also sent from the upper electronic module (UEM) (4/70) to the rear electronic module (REM). The lamps (10/173 (XC90)) are then powered directly from the rear electronic module (REM).

For the XC90, the roof lamp in the cargo compartment also lights..

Scheme 252

When a power consuming component is connected to the rear 12V socket (17/19), the power consumption is measured via a shunt inside the rear electronic module (REM) (4/58). The rear electronic module (REM) transmits status data via the controller area network (CAN) to the driver information module (DIM) (5/1) which displays a text message.

The text message is also displayed if a power consuming component is connected when changing from ignition position

1. II to I
2. I to 0 and
3. 0 to the key is removed.

There is also an audible warning note when the key is removed.

Scheme 253

The parking assistance system warns the drivers of close objects when reversing.

The driver is warned by a sound signal from the loudspeakers for the audio module (AUM) (16/1). The signal is transmitted via the infotainment control module (ICM) (16/94).

The rear sensors (7/131, 7/132, 7/133 and 7/134) are active when the ignition is on in position II and back-up gear (R) is selected. The sensors are deactivated automatically when the gear selector lever is moved from R to any other position. The sensors detect objects at a distance of 1.5 meters. A beeping sound is heard from the rear right-hand loudspeaker (16/5). The sound signal becomes more frequent as the distance to the object reduces. The sound is constant at distances below approximately 30 cm.

The front sensors (7/204, 7/205, 7/206 and 7/207) (option) are active when the ignition is on in position II and gear R is selected, or when the ignition is on in position II and the car is driven forwards at speeds below 10 km/h. The sensors are automatically deactivated when the car is driven forwards at above 15 km/h. On cars with automatic transmissions, the sensors are deactivated if P is selected, irrespective of speed. The sensors detect objects at a distance of 0.8 meters. A beeping sound is heard from one of the front loudspeaker on the driver's side (16/4). The sound signal becomes more frequent as the distance to the object reduces. The sound is constant at distances below approximately 30 cm.

A signal is transmitted from the parking assistance module (PAM) (4/86) to the rear electronic module (REM) (4/58). This indicates whether the buzzer should be switched on or off.

The rear electronic module (REM) then transmits a signal to the audio module (AUM) on the controller area network (CAN). This signal is sent to the Infotainment Control Module (ICM).

If a trailer or caravan is connected, the parking assistance system must be deactivated. This is done using the switch on the climate control module (CCM) (3/112).

The climate control module (CCM) then transmits a signal to the rear electronic module (REM) via the controller area network (CAN). The parking assistance system is deactivated.

Scheme 254

The trailer module (TRM) (4/110) ensures that the correct type of signals are transmitted to the tow hitch cable harness.

The rear electronic module (REM) (4/58) receives messages on the controller area network (CAN) from the central electronic module (CEM) (4/56) about when output signals to the turn signal lamps, parking lamps, back-up lamps and fog lamps should be activated. The rear electronic module (REM) then transmits a direct signal to the trailer module (TRM).

The trailer module (TRM) forwards the signal to the tow hitch cable harness.

The +12 V output signal is activated when the ignition key is turned from position 0 to I, II or III. The rear electronic module (REM) transmits the signal.

+12 V supply is direct from the battery.

The rear electronic module (REM) transmits messages on the controller area network (CAN) to the central electronic module (CEM) and driver information module (DIM) (5/1), if a trailer is connected to the tow hitch connector socket. A separate indicator lamp in the driver information module (DIM) indicates when the turn signal lamps are used and the trailer is connected. If one of the turn signal lamp bulbs is defective the separate indicator lamp will not light.

The output signals for back-up lamps, fog lamps and +12 V in the socket for the tow hitch connector are market dependent. The socket for the tow hitch connector is available in a number of variants with different numbers of pins.

Scheme 255

The rear window lift mechanisms are operated using switches (3/85-86) in the door panels.

When the window lift mechanisms are operated from the driver's position, data is transmitted from the driver's door module (3/126) via the controller area network (CAN) to the rear electronic module (REM) (4/58) which transmits a signal to the correct relay.

There is a switch in the driver's door module (DDM) to allow for child locking, where the windows can only be operated from the driver's position. When the function is active, information is transmitted via the controller area network (CAN) to the rear electronic module (REM) to disconnect the relay. The circuit for the rear switch is then broken.

When the child lock is activated, the lighting in the rear switches goes out.

Scheme 256

The rear electronic module (REM) handles functions for

1. alarm (certain functions)
2. locks (certain functions)
3. Inclination Sensor Module alarm
4. siren (XC90 structure week 201128-)
5. headlamp range adjustment position sensors (Bi-Xenon)
6. fuel level (Bi-fuel)
7. shut-off valve (Bi-fuel)
8. rear fog lamps
9. back-up lamp
10. stop lamps
11. high level stop lamp
12. rear windshield wiper/washers
13. rear demist
14. cargo compartment lighting
15. rear 12 V socket
16. parking assistance system
17. electrical connections on the tow hitch
18. rear parking lamps/license plate lighting
19. rear window lift mechanisms.

The control module is installed as a separate unit in the rear relay box. This is under the left-hand cargo compartment panel.

The rear electronic module (REM) communicates with components which are directly connected and also 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 using an integrated diagnostic system A diagnostic trouble code (DTC) is stored if the control module detects an error. In certain cases the control module replaces the faulty signal with a substitute value.

Any diagnostic trouble codes (DTCs) are stored in the control module memory. This information can be read off using VIDA via the data link connector in the vehicle.

Lock and unlock the rear doors to check whether the rear electronic module (REM) is grounded and powered. The control module is powered and grounded if the doors lock and unlock. Another way to check whether the rear electronic module (REM) is powered and grounded is to switch on the rear fog lamp.

The following table summarizes input signals to and output signals from the rear electronic module (REM). The signal types are divided into directly connected signals, serial communication and controller area network (CAN) communication. The illustration below displays the same information with the Volvo component designations.

Scheme 257

Scheme 258

The rear seat entertainment module (RSE) is enclosed in a steel casing with installation holes. In the XC90, it is located below the centre console between the driver's and passenger seat. The control module is driven from Ext. X-feed in the central electronic module (CEM).

The central unit of the rear seat entertainment system is the rear seat entertainment module (RSE), which interprets and implements the commands issued by the user via the system's infrared remote control. These commands are forwarded to the rear seat entertainment module (RSE) via the system's infrared receiver in the screens. The rear seat entertainment system (RSE) also distributes current to the system and detects the status of the vehicle ignition via a sensor lead that runs from the control module to the vehicle ignition switch. This prevents battery consumption when the vehicle is not in use.

The rear seat entertainment module (RSE) receives audio and video signals from the DVD player and the vehicle's TV receiver (if installed). It is also possible to receive additional input audio/video and output a two-channel audio output at low level via the AUX inputs.

Scheme 259

The rear audio separation module (RAS) is enclosed in a casing of ribbed aluminium with installation holes.

The rear audio separation module is a unit with dual functions. The first is the production of continual infrared signals via "control module infrared transfer" for "wireless headphones" (audio is in headphone mode as standard). The second is integration with the vehicle's rear speakers for media selection.

Scheme 260

The multimedia head restraint consists of five main components

1. Screen
2. Circuit board
3. Rear piece
4. Border
5. Head restraint pad

The rear piece is fastened in an opening on the rear of the head restraint pad. The circuit board is held in place in the rear piece with three screws. The screen is housed in the rear piece in front of the circuit board and is connected with a flexible foil cable and an AC lead. The border holds all electronic components in place in the rear piece in the head restraint pad. The lower edge of the border contains a window so that the infrared receiver on the circuit board can receive infrared signals from the remote control. The infrared receiver is separately connected to the rear seat entertainment module (RSE) and is activated when the rear seat entertainment module (RSE) is on.

The 7-inch screen has an aspect ratio of 16:9. The screen is positioned to provide the optimal viewing angle. The screen has a 120 degree horizontal viewing angle.

The integrated infrared receiver is activated when the rear seat entertainment module (RSE) is supplied power. The screen is activated once the receiver obtains an infrared "switch-on command" from the remote control. The circuit board contains an image generator, an infrared receiver and a unit that controls all screen settings

1. colour
2. contrast
3. brightness
4. aspect ratio.

Contrast control has a contrast ratio of 30:1 to improve the image and reduce sharp light from bright daytime conditions down to complete darkness. Brightness can be adjusted so that the image on the screen is clear even in daylight. The circuit board is also responsible for voltage protective and the power supply to the screen's background illumination. The control module contains logic for interpreting commands for setting video output, input selections and background illumination brightness.

The screens are supplied power and grounded via the rear seat entertainment module (RSE).

Scheme 261

The DVD player has a compact chassis and border in miniature format that is ideal for tight installation locations (148 mm x 55 mm x 160 mm). The DVD player has standard ISO connections. Its mechanism is resistant to vibrations and works to avoid the image or audio becoming choppy during playback. The DVD player has slot-in disc feed with region coding programmed into the software. The DVD player has video output in NTSC or PAL format depending on the format of the DVD disc. The player is completely integrated with the rear seat entertainment system and is controlled with the infrared remote control via the rear seat entertainment module (RSE). The operating temperature of the player is -20 to +70 °C.

Introduction of a new DVD player is planned for week 5 2005. The new and improved DVD player can read DVD-R/+R, DVD-RW/+RW, CD-R and CD-RW discs and can play MP3 files. The "+" and "-" buttons can now be used to change chapters in a DVD movie or jump to the next track on a CD.

The DVD player is supplied power and grounded via the rear seat entertainment module (RSE).

Scheme 262

The wireless IR headphones are compatible with both screens. IR transfer is used to transfer standard audio to the headphones in two-channel stereo format. The headphones are powered by internal batteries. The headphones are switched on with a button on one side while the volume of the respective headphones is adjusted with a wheel. Each set also has a channel selector that controls which audio source the set of headphones receives.

Scheme 263

The rear of the centre console (XC90) houses an AUX panel with external input connections for audio/video. This input can be used for inputting standard AV signals to the system. Such signals include video camera, Dreamcast, Nintendo, Playstation, Playstation 2, VHS videotapes, portable DVD or CD player.