hi guys. i have a 2001 au fairmont wagon. 6 and auto. when i bought it, i noticed the following,

-it would randomly go into limp home with the transmission.
-the air con would randomly drop out after a while.
-abs and traction control lights on.

i bought a cheap obd2 adaptor and used forscan. it told me i had a d**k solenoid in the trans. checked it when it was playing up, found the failed solenoid and replaced it. serviced the trans while i was at it. so far so good.

it also said the a/c pressure was low. ended up the clutch was slipping. changed the clutch and again, so far so good.

the last thing is the traction control. it keeps coming up now with code p1221. this is tied up with the vss apparently ? i've checked all the wheel speed sensors and when each wheel was spun in turn it produced a voltage. the vss appears to work, as the speedo works and the auto shifts.

it was suggested to me that the ecm may be faulty. i was also led to believe that with smartshield it's a case of having a ford dealer or someone with a compatible scan tool marry up the ecm with the other modules. is this true ?

can anyone shed any light on this for me ?

Sometimes if the battery is low or charge is low it can cause the traction control light to show and also cause other electrical headaches for you.

i think they're both ok. fires up pretty easy all the time. i'll check though. any other suggestions if that's not the culprit ?

if you change ECM a parameter relearn has to be done to relink BEM to ECM -
check that all tyre pressures are correct and tyres are same size/wear
check connection into abs module check power and earth to ABS module for poor connection/supply

A known thing that causes issues with both ABS and traction control is dud coilpacks or leads believe it or not.
I had the issue with my Missus's AU3 5.0 Ghia and Troyman had the same issue with his missus's AU2 4.0 Ghia.
Both the exact same issue at different times and both the exact same fix.
Neither of us could believe it but that's what it was.