I had a post about how my Volvo was not starting. I brought the battery to a local mechanic and had it charged just to get the car started to see how it ran. Because it was given to me by my grandmother. I just barely got it started by jumping it. The power-steering did not work properly, the speedometer did not work, has an airbag message is on, and ABS message on, a check engine light on, brake light is on, and the car feels very very underpowered. As if it's in some sort of safe mode or something? Does the ECU need to be re-flashed? What should I do? Please help!

 

First thing is to get a fresh new battery. I would assume that if you barely got the car to turn over, your battery doesn't have enough volts to keep other systems up and running properly. Check your alternator to see if that is Charging/working properly.
Scan your car for codes to see if there is any. This will pinpoint your problem. I suspect a bad ABS module/speed sensor.