P1921
Symptom: CHECK GEARBOX warning lamp is on. TCM in Limp-Home mode.
P1921 |
Fault symptoms
CHECK GEARBOX warning lamp is on.TCM in Limp-Home mode.
Conditions
This DTC is generated when diagnostic communication between Trionic and TCM ceases. This takes place when the speed exceeds 200 rpm and the fault has been present for more than 6 seconds.Diagnostic help
The TCM goes into Limp-Home mode.If Trionic is not present on the bus, the car will not start.