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Home >> Volvo >> 1998 >> C70 2D Convertible, Automatic >> Repair and Diagnosis >> Engine Performance >> Engine Control Systems >> Engine Control System - Removal & Installation, System Checking (Convertible) >> Control modules Control area network (CAN) >> Control modules
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Control modules

Fig 1: Identifying Controller Area Network Components
GLL105868Courtesy of VOLVO CARS OF NORTH AMERICA.

The number of control modules in the CAN varies depending on the level of equipment, the car model and the structure week. The description applies to the structure week 199815-200149. The structure week and the manufacture week are not necessarily the same week. The week of manufacture is the week in which the car was manufactured in the factory. The content of the car is guided by the structure week A structure week can extend over many manufacture weeks. The structure week is specified in the format YYYYWW.

For example, the structure week 199815 indicates that the structure week of the car is week 15 1998.

Explanation
LS CAN = CAN Low speed section (125 Kbps)
HS CAN = CAN High speed section (250 Kbps)
Serial = Serial communication (Volcano Lite) between the slave control module and the Controller area network (CAN) control module (10.4 Kbps).
Slave control module = A control module with low computing power which is connected to a main "control module" and which only operates on commands from the main control module.
Option = Accessories installed at the factory to order, when purchasing a new car.
Accessories = After market installations.
Control module Name/ Function Communication Other
ABS  Anti-Lock Brake System Module. HS CAN Replaced by the brake control module from structure week 200135 inclusive.
  Controls the brake system ABS/EBD/DSTC/STC functions and communicates with the other modules via the network high speed sector. Contains a terminating resistor for the network.
Replaced by the brake control module from structure week 200135 inclusive.
AEM  Accessory Electronic Module. LS CAN Accessories
  Controls certain accessory functions for the car. The control module communicates with other control modules via the low speed sector of the network.
Audio control module  Audio Module. LS CAN Standard/ accessory/option.
  Controls the radio / audio equipment and communicates with the other modules via the network low speed sector.
Brake control module  Brake Control Module HS CAN Replaces the ABS control module from structure week 200135.
  Controls the ABS/EBD/DSTC/STC functions of the brake system and communicates with the other modules via the network high speed sector. Contains a terminating resistor for the network.
Replaces the ABS control module from structure week 200135.
Climate control module  Climate Control Module LS CAN STD/ MCC/ ECC
  Controls the climate control system functions and communicates with the other modules via the network low speed sector.
Central electronic module  Central Electronic Module HS CAN/ LS CAN
  Is the network main control module and the interface between the high and low speed sides. The control module has a comprehensive function in the electrical system and handles a large number of functionalities.
Additional heater module  Combustion Preheater Module Serial Option /accessory.
Market dependent
  Start the parking heater. The combustion preheater module is a slave control module for the central electronic module and communicates serially. Slave control module for the central electronic module (CEM).
Driver's door module  Driver Door Module LS CAN
  Controls the drivers door functions and communicates with the other modules via the network low speed side.
DEM  Differential Electronic Module HS CAN Option from structure week 200135 inclusive.
  Controls four wheel drive engagement and communicates with the other modules via the network high speed side.
Driver information module  Driver Information Module LS CAN
  Controls the combined instrument panel functions and communicates with the other modules via the network low speed side.
Engine control module (ECM)  Engine Control Module HS CAN Different versions depending on the engine alternative.
  Controls the engine functions and communicates with the other modules via the network high speed side. Contains a terminating resistor for the high speed side on the network for those engines which do not have an electronic throttle module.
Electronic throttle module  Electronic Throttle Module HS CAN Gasoline engines only.
  Controls the throttle and communicates with the other modules via the network high speed side. Contains a terminating resistor for the high speed side on the network. A design change has been introduced structure week 200135 on certain gasoline engines. The electronic throttle module has been replaced by a new type of electronic throttle which does not communicate using the controller area network (CAN).
GSM  Gear Selector Module Serial Slave control module for the transmission control module (TCM).
  Transmits and receives information about the position of the gear selector and the lighting strength in the gear selector. The gear selector module is a slave control module for the transmission control module (TCM) and communicates serially. Applies to cars with automatic transmission only.
Inclination Sensor Module  Inclination Sensor Module Serial Option /accessory.
Slave control module for the rear electronic module (REM).
  Used for the alarm, transmits information about the angle of the vehicle. The inclination sensor module is a slave control module for the rear electronic module and communicates serially.
LSM  Light Switch Module Serial Slave control module for the central electronic module (CEM).
  Transmits information about the light switch beam level adjustment and rheostat positions, and status of the switches. The light switch module is a slave control module for the central electronic module and communicates serially.
Mass Movement Sensor  Mass Movement Sensor Module Serial Option /accessory.
Slave control module for the upper electronic module.
  Used for the alarm, transmits information about movement in the passenger compartment The mass movement sensor module sensor is a slave control module for the upper electronic module and communicates serially.
Passenger door module  Passenger Door Module LS CAN
  Controls the functions in the passenger side door and communicates with the other modules via the network low speed side.
Carphone module  PHone Module LS CAN Option /accessory.
  Controls the functions of the carphone and communicates with the other modules via the network low speed side.
Power seat module  Power Seat Module LS CAN Standard/ option
  Controls the positions and functions of the driver's seat. Communicates with other control modules via the low speed side on the network.
NOTE:

Power seat module (PSM) does not check the seat heating and SIPS (side impact protection system) airbag function.

Rear electronic module  Rear Electronic Module LS CAN
  Controls the electrical functions in the rear section of the car, and communicates with the other modules via the low speed side on the network.
Contains a terminating resistor for the network.
RTI (road traffic information)  Road Traffic Information Module LS CAN Option /accessory
  Controls the road traffic information functions and communicates with the other modules via the low speed side on the network.
Steering angle sensor  Steering Angle Sensor Module HS CAN Option.
Used in the DSTC system.
  Collects information about the steering angle and communicates with other control modules using the high speed side on the network.
Siren control module  Siren Control Module Serial Option /accessory.
Slave control module for the upper electronic module.
  Controls the siren and functions. The siren control module is a slave control module for the upper electronic module and communicates serially.
SRM  Sun Roof Module Serial Option.
Slave control module for the upper electronic module.
  Controls the sun roof and functions. The sun roof control module is a slave control module for the upper electronic module and communicates serially.
SRS (supplemental restraint system)  Supplemental Restraint System Module LS CAN
  Controls the crash safety system and communicates with the other modules via the low speed side on the network.
Steering wheel module  Steering Wheel Module LS CAN
  Receives signals from the switch in the steering wheel and the controls around the steering wheel.
Communicates with other control modules via the low speed side on the network.
Transmission control module (TCM)  Transmission Control Module HS CAN Applies to cars with automatic transmission only.
  Controls the automatic transmission and communicates with the other modules via the high speed side on the network.
Upper electronic module  Upper Electronic Module LS CAN Included in the rear view mirror.
  Controls the electrical functions in the upper section of the passenger compartment. Communicates with other control modules via the low speed side on the network.
Contains a terminating resistor for the network.
NOTE:

There are two versions of the upper electronic module. One with automatic anti-glare function and one without. The two versions cannot be interchanged.