Hey there. My Volvo has been giving me a headache. So I already know my fuel pump is going out soon. But I started it and parked it in my shop. Now I’ve been fixing this thing for a while and I’ve replaced a lot of parts chasing all the codes. And I got down to one code. A P0015
and then I took it around the block and several other codes popped up. Talking about the computer failure and other stuff hinting towards the ECU. So I don’t know much about ECUs so I just replaced it. Now my car won’t start. I’m going to try it tomorrow but I’m having doubts. Did I do something wrong?

 

what year is your car? If its a gen2 S40 most likely your ECU is paired to other computers and you'd need some VIDA programming done. That said, I'd simply reinstall the original ECU. The P0015 is a camshaft position warning. This can have several causes - a wonky CAM position sensor, the timing belt jumped a notch or two or you have VVT issues. Common VVT issues are a wonky solenoid or the actuator or VVT gear has become gunked up (the VVT uses oil pressure so if the car is high mileage and did not get regularly serviced with synthetic oil). When was the last time the timing belt was serviced?

 

Yes - you installed a ECU that is not "paired" to the other control units in the car. A company such as xemodex.com can transfer your old ECU program to a correct part number used ECU if you want. VIDA is not capable of making used control units work in different cars.

The ECU is not your problem though - as another has mentioned your 0015 is a cam timing code -

Don't know what your diagnostic process is - but part swapping can be pretty frustrating, and expensive.