That message persists when you have manually activated the retarder. Check your settings for the retarder increase/decrease keys and hit the decrease key in-game for a few times. As far as I understand, this is a bug. If you press the apostrophe key, it should go away.

Originally posted by Roane Gaming: Just a heads up, if you're experiencing this bug DON'T waste your time putting your settings back to default, just keep pressing the decrease retarder button until the message disappears and your cruise control will work again. Showing 1 - 9 of 9 comments. Qrazy Nov 30, 2023 @ 3:44pm. So change the keybindings.
The term retarder is often used broadly and includes engine/exhaust brakes (Jake brakes) and dedicated hydraulic systems. In the game, retarder refers to hydraulic retarders and these are actually fairly uncommon in the US. They work by either being a part of the transmission itself, or attached to an accessory shaft on the transmission.
Learn how to disable the retarder in Euro Truck Simulator 2 with this comprehensive guide. Follow step-by-step instructions to customize your gaming experience. Deselect the "Automatic" options for both, and you can use keyboard commands, or any reassignments you like to a peripheral device's buttons. MANUAL MODES - Exhaust Brake By default it is activated while pressing the "B" key, which must be held down for the desired duration of the braking effect. Release the "B" key, and the Exhaust Brake is no . 10 392 377 38 223 495 484 148

euro truck simulator 2 retarder activated