Esc flashing

[Chop chop]

Have charged saddle pack battery but when connecting to car, I get a constant orange and flashing red light on the speed passion esc which looking at the manual shows low voltage and overheating. Any ideas what might be causing it.

Have a durango 210 rtr. Did work fine, I have changed engine to mid motor and connected to gens ace battery and now keep getting this light.

Help .....:confused: