PLEASE HELP! GE Wall Oven problem

Oven may or may not heat. This is intermittent. No fault codes are displayed. When it does heat, temp rises no higher than 200 deg. Will not warm on self clean either but door locks properly. Timer and display read normal. I cut power completely to try reset, but still won’t operate. Could it be anything else but the control unit? I can do a simple plug-in replacement, but parts sites say that wiring may be different than the original control… Please help.