The PCM monitors various parameters and will not allow Traction Control/Active Handling (if equipped with RPO JL4) operation if any parameter falls beyond a predetermined value.
A malfunction has been detected by the PCM. The PCM then causes TCS/Active Handling shutdown until the malfunction has been corrected.
This is a temporary operational malfunction.
TCS/Active Handling (if equipped with RPO JL4) are disabled.
| • | Indicators that turn on: | 
| Car Icon (TCS indicator) | 
| • | Messages displayed on the DIC: | 
| Service Traction System | 
| Service Active HNDLG (if equipped with RPO JL4) | 
| • | Condition for DTC is no longer present and scan tool clear DTC function is used. | 
| • | Fifty ignition cycles have passed with no DTCs detected. | 
This code is for information only. It indicates there are no problems in the ABS/TCS/Active Handling system, is used as an aid to the technician.
Step  | Action  | Value(s)  | Yes  | No  | 
|---|---|---|---|---|
1  | Was the Diagnostic System Check performed?  | --  | ||
2  | 
 Are any other DTC(s) set?  | --  | ||
3  | Is DTC C1278 set as a current code?  | --  | ||
4  | 
 Did DTC C1278 set in the last three drive cycles?  | --  | ||
5  | Perform a Powertrain OBD System Check. Refer to Powertrain On Board Diagnostic (OBD) System Check in Engine Controls. Did vehicle pass the OBD System Check?  | --  | Go to Diagnostic Aids  | Go to Powertrain On Board Diagnostic (OBD) System Check in Engine Controls  |