If the BRAKE and ABS warning lights comeon at the same time, this could indicate afault in the brake system.

If the BRAKE and ABS warning lights comeon at the same time, this could indicate afault in the brake system.  - Instrument panel - Instruments and controls - Volvo XC90 Owners Manual - Volvo XC90

Stop the vehicle in a suitable place and switch off the engine.
Restart the engine.
If both warning lights go off, no further action is required.
If both lights are still on after the engine has been restarted, switch off the engine again and check the brake fluid level (see page 218 for the location of the brake fluid reservoir).

If the brake fluid level is above the MIN mark, drive carefully to a trained and qualified Volvo service technician and have the brake system inspected.

WARNING
If the fluid level is below the MIN mark in the reservoir or if a Brake failure Service urgent message is displayed in the text window: DO NOT DRIVE. Have the vehicle towed to a trained and qualified Volvo service technician and have the brake system inspected.

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