2003 Volvo V70 T-5, StandardFACTORY OEM SERVICE PROCEDURE

System overview: Signals

The chart below summarizes the input signals to and output signals from the central electronic module (CEM). 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.

Input signals Output signals
Directly connected:  Directly connected: 
  • Back-up (reversing) lamp switch (3/10)
  • Windshield wiper motor (6/1)
  • Windshield washer level sensor (7/5)
  • Horn switch (3/37)
  • Stop lamp switch (3/9)
  • Control signal P/N position, gear selector module (GSM) (3/156) (automatic transmissions only)
  • Supplemental restraint system module (SRS) (Airbag OK) (4/9)
  • Gear-shift position sensor (8/37)
  • Antenna ring, immobilizer (16/65)
  • Hazard warning signal flasher switch (3/6)
  • Fuel level sensor (7/130, 7/143) (Gasoline/diesel)
  • Seat position sensor driver (3/255-256) (XC90 USA/CDN only)
  • Twilight sensor (7/12)
  • Sun sensor (7/12).
  • Starter motor (6/25)
  • Headlamp range adjustment (6/38-39) (certain markets)
  • Windshield wiper (6/1)
  • Washer motor (6/127)
  • Horn (16/10-11)
  • Stop lamps via the rear electronic module (REM) (4/58)
  • Fuel pump (FP) (6/33)
  • Hazard warning signal flasher switch (3/6)
  • Glove compartment lighting (10/29)
  • Ignition switch lighting (16/65)
  • Courtesy lighting (10/125-126)
  • 12 V socket (9/25)
  • Auxiliary lamps (10/65, 10/66)
  • High beam (10/64, 10/68)
  • Low beam (10/66, 10/70)
  • Front parking lamps (10/11-12)
  • Turn signal lamps (10/13-14, 10/15-16, 10/47, 10/54)
  • Front fog lamps (10/5-6)
  • Electrical power steering module (EPS) (4/99).
Via serial communication:  Via serial communication: 
  • Combustion preheater module (CPM) (4/7) (optional extra)
  • Light switch module (LSM) (3/111)
  • Steering wheel module (SWM) (3/254)
  • Alternator control module (ACM) (6/26).
  • Blind spot information system (BLIS) (6/62, 6/63) (optional extra)
  • Combustion preheater module (CPM) (4/7) (optional extra)
  • Light switch module (LSM) (3/111)
  • Steering wheel module (SWM) (3/254)
  • Alternator control module (ACM) (6/26).
  • Blind spot information system (BLIS) (6/62, 6/63) (optional extra)
Via Controller Area Network (CAN) communication:  Via Controller Area Network (CAN) communication: 
  • Accessory electronic module (AEM) (optional equipment) (4/78)
  • Audio module (AUM) (16/1) (not XC90)
  • Brake control module (BCM) (4/16)
  • Climate Control Module (CCM) (3/112)
  • Driver door module (DDM) (3/126)
  • Differential electronic module (DEM) (optional equipment) (4/82)
  • Driver information module (DIM) (5/1)
  • Engine control module (ECM) (4/46)
  • Electronic throttle module (ETM) (4/50)
  • Passenger door module (PDM) (3/127)
  • Phone module (PHM) (optional equipment) (16/60)
  • Power seat module (PSM) (4/52)
  • Rear electronic module (REM) (4/58)
  • Road traffic information module (RTI) (16/45) (optional equipment, not XC90)
  • Steering wheel angle sensor module (SAS) (3/254)
  • Supplemental Restraint System Module (SRS) (4/9)
  • Transmission Control Module (TCM) (4/28)
  • Upper electronic module (UEM) (4/70)
  • Suspension module (SUM) (4/84) (optional extra)
  • Infotainment control module (ICM) (16/94) (XC90 only)
  • Data link connector (DLC) (17/13).
  • Accessory electronic module (AEM) (optional equipment) (4/78)
  • Audio module (AUM) (16/1) (not XC90)
  • Brake control module (BCM) (4/16)
  • Climate Control Module (CCM) (3/112)
  • Driver door module (DDM) (3/126)
  • Differential electronic module (DEM) (optional equipment) (4/82)
  • Driver information module (DIM) (5/1)
  • Engine control module (ECM) (4/46)
  • Electronic throttle module (ETM) (4/50)
  • Passenger door module (PDM) (3/127)
  • Phone module (PHM) (optional equipment) (16/60)
  • Power seat module (PSM) (4/52)
  • Rear electronic module (REM) (4/58)
  • Road traffic information module (RTI) (16/45) (optional equipment, not XC90)
  • Steering wheel angle sensor module (SAS) (3/254)
  • Supplemental Restraint System Module (SRS) (4/9)
  • Transmission Control Module (TCM) (4/28)
  • Upper electronic module (UEM) (4/70)
  • Suspension module (SUM) (4/84) (optional extra)
  • Infotainment control module (ICM) (16/94) (XC90 only)
  • Data link connector (DLC) (17/13).
Fig 1: CEM Devices (1 Of 2)
GLL149853Courtesy of VOLVO CARS OF NORTH AMERICA.
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