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Home >> Volvo >> 2002 >> V70 XC >> Repair and Diagnosis >> Engine Performance >> Engine Control Systems >> Bulbs, Control Modules, Charging - Design And Function >> Engine Control Module (ECM) (B5244S; 2003-2007) >> System overview >> Signals
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System overview: Signals

The chart below summarizes the input signals to and output signals from the Engine Control Module (ECM). The signal types are divided into directly connected signals and CAN communication. The illustration below displays the same information with the Volvo component designations.

Input signals Output signals
Directly connected:  Directly connected: 
  • Ignition switch (3/1)
  • Air conditioning (A/C) pressure sensor (7/8)
  • Stop lamp switch (3/9)
  • Accelerator pedal (AP) position sensor (7/51)
  • Electronic throttle unit (6/120)
  • Camshaft position sensor, intake (7/172)
  • Camshaft position sensor, exhaust (7/173) (certain markets only)
  • Engine coolant temperature (ECT) sensor (7/16)
  • Engine speed (RPM) sensor (7/25)
  • Fuel pressure sensor with integrated fuel temperature sensor (7/156) (vehicles with demand controlled fuel pumps only)
  • Knock sensor (KS) (7/24)
  • Mass air flow (MAF) sensor/temperature sensor (7/17)
  • Manifold absolute pressure (MAP) sensor (7/81)
  • Oil pressure switch (7/6)
  • Front heated oxygen sensor (HO2S) (7/15)
  • Rear heated oxygen sensor (HO2S) (7/82)
  • Oil level sensor (7/35) (2005-, certain markets only)
  • Clutch pedal sensor (7/123) (manual transmissions only)
  • Outside temperature sensor (7/105)
  • Engine coolant level sensor (7/73)
  • Ignition coils (20/3-7)
  • Engine cooling fan (FC) control module (4/71)
  • Leak diagnostic unit (6/67), (certain markets only).
  • Air conditioning (A/C) relay (2/22)
  • Electronic throttle unit (6/120)
  • Engine cooling fan (FC) control module (4/71)
  • Evaporative emission system (EVAP) valve (8/18)
  • Injectors (8/6-10)
  • Fuel pump control module (4/83) (only vehicles with demand controlled fuel pumps)
  • Ignition coils (20/3-7)
  • Leak diagnostic unit (6/67), (certain markets only).
  • Front heated oxygen sensor (HO2S), preheating (7/15)
  • Rear heated oxygen sensor (HO2S), preheating (7/82)
  • Main relay (system relay) (2/32)
  • Camshaft reset valve (CVVT), intake (8/19)
  • Camshaft reset valve (CVVT), exhaust (8/81) (certain markets only)
  • Emissions warning lamp (5/1)
  • Control module cooling fan (6/44).
Via Controller Area Network (CAN) communication:  Via Controller Area Network (CAN) communication: 
  • Transmission Control Module (TCM) (4/28) (only cars with automatic transmissions)
  • Brake control module (BCM) (4/16)
  • Central electronic module (CEM) (4/56).
Via central electronic module (CEM) (4/56):
  • Climate Control Module (CCM) (3/112)
  • Data link connector (DLC) (17/13)
  • Driver information module (DIM) (5/1)
  • Steering wheel module (SWM) (3/254).
  • Transmission Control Module (TCM) (4/28) (only cars with automatic transmissions)
  • Brake control module (BCM) (4/16)
  • Central electronic module (CEM) (4/56).
Via central electronic module (CEM) (4/56):
  • Climate Control Module (CCM) (3/112)
  • Data link connector (DLC) (17/13)
  • Driver information module (DIM) (5/1)
  • Steering wheel module (SWM) (3/254).
Fig 1: Identifying Engine Control Module Input And Output Signals (1 Of 2)
GLL147240Courtesy of VOLVO CARS OF NORTH AMERICA.
Fig 2: Identifying Engine Control Module Input And Output Signals (2 Of 2)
GLL147241Courtesy of VOLVO CARS OF NORTH AMERICA.