I NEVER allow my equipment to stay in my car during our really hot times of the year. Occasionally I will drop off my equipment at the gig site and go about my daily routine and return later to play the gig. When we have really hot weather like it is now when I drive to a gig I lower the back seats of my car so the trunk can get cool air from my A/C and that has worked well.

Unless you can afford to pay for a replacement keyboard I just wouldn't do it.

Deane