Purchased a used Nissan electric CYM02L25S forklift during summer 2019. As of recent, the forklift randomly won't engage in forward or reverse gear. Took the gear selector off and contacts looks good and clean. Removed the rear panel and all components look good. After installing the panels back on, forklift went into gear for the next 3 days, then decided to randomly not work again.

I'm not very familiar with this unit. Doing an internet search, some mention a damaged solenoid. Any thoughts or ideas? Thanks in advance!