Fig 1: Electrical Modules

Courtesy of VOLVO CARS OF NORTH AMERICA.

The central locking system includes a number of functions. The main unit of the system is the rear electronic module (REM) (4/58). The rear electronic module (REM) communicates with the internal components both via direct connections and the CAN network.

The functions covered are:

standard locking function
2 stage locking function
deadlocking
private locking mode
child safety locks
unlocking the trunk lid/tailgate
unlocking the fuel tank filler cover
indication of the status of the doors and hatches
automatic locking function
re-locking.

After the battery has been disconnected the central locking system must be initialized. This can be performed by locking and unlocking once with the key in the driver's door or with the remote control. This is performed to ensure that the status for lock motors and doors is operative.

The locking function on the vehicle at delivery depends on the market and is stored in the vehicle's configuration file, which is stored in the central electronic module (CEM). The configuration can be read via VIDA Vehicle communication.

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: General

Use the Manual With the Right Hardware

When to See a Mechanic

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