The chart below summarizes input and output signals to and from the power seat module (PSM) (4/52). 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:
Control panel (3/26) with: Control buttons (eight input signals, two buttons) Memory button 1, 2 and 3 Programming button (MEM). Hall sensors (four integrated into the seat motor) Control circuit connected to the control panel.	Seat motors (6/16-19) (four units).
Via Controller Area Network (CAN) communication:	Via Controller Area Network (CAN) communication:
Central electronic module (CEM) (4/56) Upper electronic module (UEM) (4/70).	Driver door module (DDM) (3/126) Passenger door module (PDM) (3/127).

Fig 1: Identifying Power Seat Module (PSM) Input And Output Signals

Courtesy of VOLVO CARS OF NORTH AMERICA.

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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