Report the behavior of the controls
Tell us if the door starts down and reverses, refuses to close or displays an indicator change. Those details help frame the assessment, but they do not prove that the sensors are the only cause.
Leave protective functions in place
Do not disconnect sensors or alter the system to force the door closed. Keep the opening clear and have the sensor arrangement, connections and opener behavior reviewed together.
Check the outcome against the model
The service should establish appropriate operation using the manufacturer’s guidance for the installed opener. If another fault is found, ask how it changes the repair scope before additional work proceeds.
Read indicator colors with the correct manual
Sensor colors are model-specific signals, not a universal green-means-good rule. For example, the LiftMaster 8500 manual identifies an amber sending-sensor light and a green receiving-sensor light. Record whether each is steady, off or blinking and use the instructions for the actual installed model. Indicator appearance does not establish that the complete reversing system operates correctly.
Your questions
Is every closing problem caused by a sensor?
No. Door movement, controls and other opener components may contribute. The diagnosis needs the complete system.
Can sensors be removed if they seem inconvenient?
No. Do not bypass a protective feature to keep using the door; arrange assessment of the fault.
Should both safety sensor lights always be the same color?
Do not assume so. Use the instructions for the installed model to interpret each indicator, and have abnormal closing behavior assessed without bypassing protection.
