TK25 Problem

After 20 years, I need to use my TK25 again. I now remember why I switched to the TK70. I takes about 4 minutes every time I need to change a tape. Now there is a hardware problem. When I insert a different tape, the tension cycle shows a flashing (left side of the front panel) green light until the cycle is complete. I am confident that the light changed to solid green in the past, but now the light stays unlit and the unit is not ready. At first, I tried to boot RT-11, but no luck. By accident, I needed to turn off the power, and then turn it back on. The TK25 power was left on and as soon as the PDP-11 started the boot cycle, the green light on the TK25 turned solid green. After RT-11 had booted from the hard drive, the TK25 is ready and everything works. Any suggestions? Controller? Drive? Cable? Since it takes 4 minutes for the tension cycle, having to boot again (less than a minute) is not a deal breaker. Also, now just a boot turns the green light on. Thank you in advance for any suggestions? Jerome Fine