Is it possible for the motor to lock if the ac compressor is not working?

Yes, it is possible for the motor to lock if the AC compressor is not functioning properly. If the compressor seizes or has internal damage, it can create excessive resistance in the engine's accessory drive system, potentially leading to the motor locking up. Additionally, if the compressor is not disengaging when the AC is turned off, it can put strain on the engine, contributing to a lock condition. Regular maintenance and inspection can help prevent such issues.