Kyosho Mini Z shops 4x4 Suzuki

Product Name: Kyosho Mini Z shops 4x4 Suzuki
Kyosho Mini Z 4x4 Suzuki Barely used, but has a small shops issue! Forward speed is quick and snappy, but reverse is very slow! I think it might be an issue with the ECU, because I tested the voltage of the motor, and the reverse voltage is significantly lower than the forward voltage. Probably an easy fix, but I am not skilled with electronics. Please let me know if you have any questions! I tried resetting the radio, but it did not help. I also tried switching in an out of trainer mode, and that did not help either. Was only used indoors with no physical scratches or damage.