Diagnostic Trouble Code (DTC) Information

Diagnostic trouble code (DTC) information TCM-P278768

Condition

Note! This diagnostic trouble code (DTC) status is an event controlled diagnostic trouble code (DTC). An event controlled diagnostic trouble code (DTC) does not mean that there is a fault in the control module when it is active, but is designed as information.

If the Transmission control module (TCM) registers that oil temperature in the transmission is too high, a signal is transmitted to the Engine control module (ECM) to reduce the engine's torque. This is to protect the gear box from too high load, which can result in internal mechanical faults.
The diagnostic trouble code (DTC) is stored if the control module detects that:
- The brake pedal depressed.
- The gear box oil temperature is the same as, or greater than, 120 °C for longer than 5 seconds.
- The gear box oil temperature is greater than 120 °C and lower than 140 °C for longer than 4 seconds.
- The gear box oil temperature is greater than 140 °C for longer than 3 seconds.
The control module's test for the diagnostic trouble code (DTC) starts in the event of:
- Engine running.

Note! The control module can only detect the fault once the test has been started and the diagnostic trouble code (DTC) is stored when the conditions are met.





Substitute value
- The engine limits the torque until the gear box oil temperature has dropped below a certain level.

Possible source
- The gear box oil has had too high a temperature for too long.
- Brake signal incorrect (shows brake active) while the vehicle is driven with high load with slipping lock-up.
- Long term revving of the engine with gear selector in position D and the brake pedal depressed.

Fault symptom[s]
- Driving/Poor performance/lacks power
- Driving/Hesitates/surges/Unsure when/at all times