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Hadn't any air bag light on dash and found three cut wires at connector B going to ECU.
1. Cut pink power wire from I51 electronic control units power supply relay pin 87 to B1 wire to pin 18 of air bag ECU.
2. Cut green wire B4 from pin 20 of ECU to air bag light icon in speedo.
3. Cut light blue-black wire B6 from ECU pon 19 to T3 test connector pin A.
So no power to ECU, no power to air bag light and no way to reset ECU with T3 test connector.
Managed to solder wires back to correct pins in B connector and then pull codes.
Got fault codes 24, 25, 26 and 42. First three all had to do with R/H forward sensor and last one for failed air bag light. Being wire cut to light no wonder.
Sensor codes went away when I reset ECU, too.
Using the Alfa tester P/N 8828 and applying the three second off/on/off rule I was lucky enough to reset the ECU first time I tried.
Note: In regards to wiring diagram in wiring manual there is some errors and TSB 45.93.05 addresses these errors which reverse yellow and red wires in sensors in wiring diagram.
1. Cut pink power wire from I51 electronic control units power supply relay pin 87 to B1 wire to pin 18 of air bag ECU.
2. Cut green wire B4 from pin 20 of ECU to air bag light icon in speedo.
3. Cut light blue-black wire B6 from ECU pon 19 to T3 test connector pin A.
So no power to ECU, no power to air bag light and no way to reset ECU with T3 test connector.
Managed to solder wires back to correct pins in B connector and then pull codes.
Got fault codes 24, 25, 26 and 42. First three all had to do with R/H forward sensor and last one for failed air bag light. Being wire cut to light no wonder.
Sensor codes went away when I reset ECU, too.
Using the Alfa tester P/N 8828 and applying the three second off/on/off rule I was lucky enough to reset the ECU first time I tried.
Note: In regards to wiring diagram in wiring manual there is some errors and TSB 45.93.05 addresses these errors which reverse yellow and red wires in sensors in wiring diagram.
