The table below summarizes the input signals to and output signals from the Engine Control Module (ECM). The signal types are divided into directly connected signals, LIN 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:
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 (CMP) sensor, intake bank 2 (7/172) Camshaft position (CMP) sensor, intake bank 1 (7/188) Camshaft position (CMP) sensor, exhaust bank 2 (7/173) Camshaft position (CMP) sensor, exhaust bank 1 (7/189) Engine coolant temperature (ECT) sensor (7/16) Engine speed (RPM) sensor (7/25) Fuel pressure sensor / fuel temperature sensor (7/156) Knock sensor (KS) (7/23-24) Mass air flow (MAF) sensor/air temperature sensor (7/17) Manifold absolute pressure (MAP) sensor (7/81) Oil pressure switch (7/6) Front oxygen sensor, bank 2 (7/15) Front oxygen sensor, bank 1 (7/82) Rear oxygen sensor, bank 2 (7/103) Rear oxygen sensor, bank 1 (7/104) Oil level sensor (7/35) Outside temperature sensor (7/105) Engine coolant level sensor (7/73) Ignition coils (20/46-53) Engine cooling fan (FC) control module (4/71) Leak diagnostic unit (6/67) (certain markets only)	Air conditioning (A/C) relay (2/22) Air conditioning (A/C) compressor (8/3) Electronic throttle unit (6/120) Engine cooling fan (FC) control module (4/71) Evaporative emission system (EVAP) valve (8/18) Injectors (8/146-153) Fuel pump (FP) control module (4/83) Ignition coils (20/46-53) Leak diagnostic unit (6/67) (certain markets only) Front oxygen sensor, bank 2 preheating (7/15) Front oxygen sensor, bank 1 preheating (7/82) Rear oxygen sensor, bank 2 preheating (7/103) Rear oxygen sensor, bank 1 preheating (7/104) Main relay (system relay) (2/32) Starter motor relay (2/35) Camshaft reset valve (Continuous variable valve timing (CVVT)), intake bank 2 (8/19) Camshaft reset valve (Continuous variable valve timing (CVVT)), intake bank 1 (8/117) Camshaft reset valve (Continuous variable valve timing (CVVT)), exhaust bank 2 (8/81) Camshaft reset valve (Continuous variable valve timing (CVVT)), exhaust bank 1 (8/118) Emissions warning lamp (5/1) Valve variable intake (8/107)
Via LIN communication:	Via LIN communication:
Alternator control module (ACM) (6/26)	Alternator control module (ACM) (6/26)
Via Controller Area Network (CAN) communication:	Via Controller Area Network (CAN) communication:
Central electronic module (CEM) (4/56) Brake Control Module (BCM) (4/16) Climate Control Module (CCM) (3/112) Rear electronic module (REM) (4/58) Transmission control module (TCM) (4/28) Steering wheel module (SWM) (3/254)	Central electronic module (CEM) (4/56) Brake Control Module (BCM) (4/16) Climate Control Module (CCM) (3/112) Rear electronic module (REM) (4/58) Transmission control module (TCM) (4/28) Steering wheel module (SWM) (3/254) Driver Information Module (DIM) (5/1)

Fig 1: Identifying Volvo Component Designations

Courtesy of VOLVO CARS CORPORATION

When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

• You smell fuel, burning insulation, or see smoke.

• Brakes feel soft, pull hard to one side, or make grinding noises.

• The engine overheats, stalls repeatedly, or misfires under load.

• You are missing required tools, torque specs, or safe lifting equipment.

• You are not confident in the next step or safety outcome.

Safety Warning

System Overview: Signals

Use the Manual With the Right Hardware

When to See a Mechanic

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