my dad just bought a 99 volvo c70 with 100k miles , it was running great for the first couple of weeks but now it seems like there is something wrong with it , the speedometer quits working whenever it feels like it , the rest of the panel works just fine , its just the speedometer ... i scanned it and the followin codes came up :
p0014 camshaft position actuator b bank 1 timing over advanced
p0237 turbo/super boost sensor a circuit low input
p0236 turbo/super boost sensor A CKT range/performance
p0722 output shaft speed sensor circuit no signal
p1618 TCM
p1633 abs
never had a volvo before and i been reading about how having a faulty ABS module might cause a lot of codes to come up, has anyone had to deal with a faultymodule , if so ... what codes does it usually cause? thanks a lot for any input that might help us....

 

Has the timing belt been replaced?
VVT soleniod might be bad.
The boost pressure sensor might be bad.

I will be the ABS module is bad. You can get it rebuilt or about $100.00.

 

Hey there,
I just happend to own a 99 c70 that had the same problem a few weeks ago (like two actually). i got a diagnostic and it and they told me that i had to replace the abs module because it just had some faults. WRONG!!
I then had to do another smog and that's where all the speed sensor stuff came out. the real problem was just the "transmission speed sensor"
You can find it under your air filter and you should make sure it isn't loose or anything like that. if it isn't then that's most likely your problem.
Check your speed sensor before doing anything. because your abs may not be faulty at all and you wouldn't want to do the same mistake as i did spending money replacing something that didn't need to be.
Also if your brake light comes on and/or your winter mode arrow...it's all because of the speed sensor. pretty cheap; like $100 and like 20 mins of labor if you need to replace it.