Checking trailer lamps

When connecting a trailer – check that the trailer lamps work before departure.

Checking trailer lamps*

Automatic checking

After a trailer is connected electrically, it is possible to check that the trailer lamps are working via an automatic lamp activation. The function helps the driver check that the trailer lamps are working before starting off.

The car must be switched off to perform the check.
When a trailer is connected to the towbar, the Automatic Trailer Lamp Check message is shown in the driver display.
Confirm the message by pressing the right-hand steering wheel keypad's O button.
The lamp check starts.
Exit the car to check lamp functionality.
All trailer lamps start to flash - then the lamps are switched on one at a time.
Visually check that all lamps available on the trailer are operational.
After a moment, all lamps on the trailer flash again.
The check is complete.

Switching off automatic checking

The automatic checking function can be switched off in the centre display.

Press Settings in the top view.
Press My CarLights and Lighting.
Deselect Automatic Trailer Lamp Check.

Manual checking

If the automatic checking is switched off then it is possible to start the check manually.

Press Settings in the top view.
Press My CarLights and Lighting.
Select Manual Trailer Lamp Check.
The lamp check starts. Exit the car to check lamp functionality.

Rear fog lamp on trailer

When connecting the trailer, the rear fog lamp may not light up on the car. In such cases, the rear fog lamp function switches to the trailer. Upon activation of the rear fog lamp, check therefore that the trailer is equipped with a rear fog lamp to travel safely.

Symbols and messages in the driver display

If one or more of the trailer's direction indicators or brake light bulbs is broken, the driver display shows a symbol and a message. Other lights on the trailer must be checked manually by the driver before setting off.

SymbolMessage
P5-XC90H-1519-Trailer turn indicator
  • Trailer turn indicator Right turn indicator malfunction
  • Trailer turn indicator Left turn indicator malfunction
P5-XC90H-1519-Trailer brake light
  • Trailer brake light Malfunction

If any lamp for the trailer's direction indicators is broken, the driver display symbol for direction indicators will also flash more quickly than normal.

  1. * Option/accessory.