Xplorer 400 starter problems

My 97 Xplorer400 has had problems starting. It will pull start just fine, I have replaced the battery and confirmed proper voltage, I have replaced the solenoid and now have replaced the starter. It still will not electric start, it tries to start but seems like there is not enough power, it only turns over a couple of times very weekly then there is a click and all power (headlight) goes off for about 5 seconds then another click lights back on but still won’t start. It will start right up when pull starting. Any ideas? what is the little power block that is in the black plastic cover above the solenoid?

Xplorer 400 starter problems

My 97 Xplorer400 has had problems starting. It will pull start just fine, I have replaced the battery and confirmed proper voltage, I have replaced the solenoid and now have replaced the starter. It still will not electric start, it tries to start but seems like there is not enough power, it only turns over a couple of times very weekly then there is a click and all power (headlight) goes off for about 5 seconds then another click lights back on but still won’t start. It will start right up when pull starting. Any ideas? what is the little power block that is in the black plastic cover above the solenoid?