DTC P0844
DTC P0844: Dog Clutch Malfunction
General Description
The transmission control module (TCM) monitors the conditions of dog clutch when shifting. If the complete engagement of dog clutch A and F cannot be confirmed for a specified time while down shifting which accompanies dog clutch A and F to engage, the TCM stores a DTC.
Monitor Execution, Sequence, Duration, DTC Type
| Execution | Continuous |
| Sequence | None |
| Duration | 1 second or more |
| DTC Type | One drive cycle, MIL off, A/T gear position indicator off |
Enable Conditions
| Condition | ||
|---|---|---|
| Vehicle | During down shifting which accompanies dog clutch A and F to engage | |
Malfunction Threshold
Following conditions occur while down shifting which accompanies dog clutch A and F to engage.
- The TCM cannot confirm complete engagement of dog clutch A and F for at least 2 times during one drive cycle.
- The TCM cannot confirm complete engagement of dog clutch A and F for at least 3 times per 1, 243 miles (2, 000 km).
Possible Cause
The causes shown may not be a complete list of all potential problems, and it is possible that there may be other causes.
- Transmission internal failure
Confirmation Procedure
Operating Condition
- 1.
Start the engine.
- 2.
Drive the vehicle from 8th gear to 7th gear or from 5th gear to 4th gear.
- Drive the vehicle in this manner only if the traffic regulations and ambient conditions allow.
- It may be difficult to reproduce the failure by the test-drive.
With the HDS
None.
Diagnosis Details
Conditions for setting the DTC
When a malfunction is detected, a Pending DTC, a Confirmed DTC, and the freeze data are stored in the TCM memory. The MIL does not come on.
Conditions for clearing the DTC
The Pending DTC, the Confirmed DTC, and the freeze data can be cleared with the scan tool Clear command.