My understanding is that the red light is a low voltage warning light. It is on when the ignition is on but the car is not running to show it is working (as on a "normal" car). It should turn off once the car is started, unless the electrical system voltage is too low. I have no awareness of the red light being used as a check engine light, but my SVT doesn't have the light connected. I use a Diablosport Predator handheld tuning programmer to check my fault codes, and I have a couple of evaporative emissions codes, a high fan speed switch code, an OBD II test incomplete code, and one or two transmission output shaft speed sensor codes. All of these are supposedly normal, due to shoe-horning a transverse, front wheel drive engine into a longitudinal, rear wheel drive car using a completely different transmission. I suppose it's a minor miracle that the engine management systems work at all, considering.