I have this focus ST which is giving me headaches and im hoping someone could point me in the right direction.
I initially looked at it for esp failure, it had these dtcs stored
C2778 sensor power supply U1901 CAN network 2 Communication bus fault , receive error B905
There was no supply to the yaw rate sensor or the steering angle sensor, so i disconnected the yaw rate sensor and the supply came back, the C2778 code went but the u1901 code stayed . Fitted a new sensor ,u code now gone, calibrated it with DEC SS3 and the car went back to the customer.
Now the esp light is on again 3 days later with these codes stored: C1277 steering angle 1+2 circuit failure U1901 CAN network 2 Communication bus fault , receive error B905 U2527 CAN network 2, bus off Transmit error.
Looking on live data i have supply to the angle sensor now which i didnt have with the faulty yaw sensor but no apparent output from the angle sensor.
Could a shorted yaw rate sensor damage the steering angle sensor ?
What should i be looking for output wise with a scope on the angle sensor?
This fault was caused by damaged wiring about 3 inches from the abs module,one of the inputs from the steering angle sensor had rubbed through on a metal bracket.