It first happened a month ago, I was driving (5 minutes from engine on) in the city and suddenly those lights/warnings went off (ASR/VDC/Steering corrector/Hill holder not available) also the throttle pedal didn't work - the engine start idleing at 1100 rpm and pressing the pedal made the engine go down to ~900 rpm, steering was 100% OK.
After it happened I pulled the car to the sidewalk, turned off the engine, turned it on again and got "Start/Stop not working" and Check engine light but the car was working perfectly.
Since then it happens at least once or twice a day, usually at the very start of the drive or at the very beginning (5 minutes tops).
I tried the following:
1. Replaced the battery with a brand new BOSCH battery (Start/Stop)
2. Went to the central dealer of alfa in my country and ask them to check the car, they said they been over and reinforced all electrical connections and replaced the fuses.
They said they couldn't find anything and said there are 2 things that are left but probably won't cause this problem:
- the left distribution motor of the climate control system is not working, I believe that I always (2nd hand car) had this problem (indicated by blinking temperature) and it never caused any problem.
- I have a custom radio that I have built, I had the system installed for a year without problems (only had to change a fuse) and now I took it off just to rule it out.
Needless to say this didn't fixed the problem.
3. Tried to find a pattern for the problem - for now I ruled out the radio system, the AC (both were off and still got the same problem) and it always happens at the beginning of the trip (up to 5 minutes) and it will be more likely to happen if the car was off for a long period.
4. Took information about the faults using AlfaOBD, faults detected (all are intermittent except the climate control one):
- (ABS) C1221 - Engine Control (NCM) Signal not valid.
- (ABS) C0074 - Torque requested on steering wheel from CAN (module DST) Signal not valid.
- (Engine) P1120 - Throttle valve position control Plausibility.
- (Steering) C100B - Torque limitation request from NFR CAN data not valid.
- (Steering) C100C - Torque requested on steering wheel from CAN CAN data not valid.
- (Body computer) B1047 - LIN serial line
- (Body computer) B1067 - Dynamic control selector on CAN.
- (Climate control) B1901 - Left distribution motor feedback, Open circuit/Short circuit to + battery.
Logs from AlfaOBD and pictures of the warning lights:
Since I don't really trust the dealers here (they are not professional in my opinion and couldn't help me) I decided to ask here if someone can help me better diagnose this problems
I know similar posts exists but I couldn't find a definitive answer.