As crazy as it may seem, check your tire pressures. We had the same issue with our red xfire and found that one tire can be low enough to set off the BAS/ESP light and not the low tire light. A slightly low tire messes with the electronic stability control. Works everytime now.
Ditto. The BAS/ESP lamp will light up if any fault is found that would/could effect your braking (BAS) or traction control (ESP). Tires that are under inflated, or are triggering a "low pressure" warning from the TPMS system in theory will affect braking and traction, hence your BAS/ESP lamp coming on. I had the same thing occuring while all the time having my "low pressure" lamp on. After replacing all the sensors when purchasing new wheels, all the warning lamps disappeared and have not returned.