After replacing Brother toner, power cycling and still getting the amber toner light. I had this particular issue with the very popular Brother HL2270DW model printer of which I’ve implemented literally 100’s.
Take all steps in exact order.
1. Open the front cover and leave open while completing the following steps.
2. Turn the printer off.
3. Hold the ‘go’ button while turning the printer on. All lights should be on.
4. Release the ‘go’ button (or “start’ button).
5. Press the ‘go’ button (or “start’ button) 2 times.
6. Pause. All panel lights should be on.
7. Press the ‘go’ button (or “start’ button) 5 times.
The toner light should be off. (error may be flashing)
The paper light should be on or flashing.
8. Close cover. The ready light should be the only light on.