DTC Advanced Diagnostics: P02CD, P02CF, P02D1, P02D3
DTC P02CD:No. 1 Cylinder Injector Offset Learning Exceeds Maximum Limit
DTC P02CF:No. 2 Cylinder Injector Offset Learning Exceeds Maximum Limit
DTC P02D1:No. 3 Cylinder Injector Offset Learning Exceeds Maximum Limit
DTC P02D3:No. 4 Cylinder Injector Offset Learning Exceeds Maximum Limit

General Description

Controlled valve operation (CVO) is a function of the powertrain control module (PCM) to determine the actual open time of injection valves. The function utilizes different signal processing algorithms to calculate rising delay and closing delay out of executed measurements. The algorithms are divided in two parts. The first part is the base adaptation and requires special injector energizing time for the measurement. The second part based on learning during normal engine operation. The needle opening duration is controlled and energizing time (feed-forward control) is adapted to the injector individually. The control variable is 'topen' and the corresponding correcting variable is the energizing time 'ti' as shown in the figure. The monitoring function verifies the calculated adjustment values of the CVO function. In case of an error, corresponding error reactions will be activated such as triggering a new base adaptation or locking the defective injector for CVO. The diagnostic utilizes different monitors in order to detect the minimum CVO errors.
Monitor 1: Rationality check of opening delay time 'tantot'
The 'tantot' value is continuously monitored against a default value. If the difference between current opening time delay (tantot) and its default value is more than a calibrated threshold, the PCM detects a malfunction and stores a DTC.
Monitor 2: CVO controller stability check
CVO controller is checked for stability during CVO basic adaptation. If the opening time of the last iteration step comparing to the previous iteration step is more than a threshold within a monitoring window, the PCM detects a malfunction and stores a DTC.
Monitor 3: Rationality check of plateau correction height
The ballistic slope correction includes a slope correction and a plateau correction parts. The measured height of the plateau correction is continuously monitored against an expected value. If the current plateau value is more than a calibrated threshold, the PCM detects a malfunction and stores a DTC.
Monitor 4: Rationality check of the total calculated injection time correction value
The calculated injection time correction is checked by the diagnostic function depending on the current working point.
In case the pulse type of the current injection is “ballistic” and the total calculated injection time correction is more than a calibrated threshold, the PCM detects a malfunction and stores a DTC.
In case the pulse type of the current injection is “full-lift” and the total calculated injection time correction is more than a calibrated threshold, the PCM detects a malfunction and stores a DTC.
Monitor 5: Rationality check of the "full-lift" closing time
This diagnostic compares the "full-lift" closing time with an expected value. If the current "full-lift" closing time 'tab' is less than a calibrated threshold, the PCM detects a malfunction and stores a DTC.
Monitor 7: Rationality check of the ballistic correction at the adjustment-point
As soon as the controller is stable at the ballistic adjustment-point, the current value of ballistic correction is transmitted to the diagnostic function. If the integrated value during base adaptation is more than a calibrated threshold, the PCM detects a malfunction and stores a DTC.

Monitor Execution, Sequence, Duration, DTC Type
Execution
Continuous
Sequence
None
Duration
0.5 second or more
DTC Type
Two drive cycles, MIL on

Enable Conditions
Common
Condition
 
State of the engine
Running

Monitor 1 and 3
Condition
 
Other
Base adaptation is active

Monitor 2
Condition
 
Other
Base adaptation is active
The controller is not stable

Monitor 4
Condition
 
Other
Base adaptation is finished

Monitor 7
Condition
 
Other
Base adaptation is active
The controller is stable during base adaption
Pulse type of current injection is "ballistic"

Malfunction Threshold
Monitor 1
Difference between current opening time delay 'tantot' and its default value is more than 150 µseconds at least 1 time.
Monitor 2
The controller cannot stabilize within 7 times of allowed measurements.
Monitor 3
The current plateau value is more than 90 µseconds at least 2 times.
Monitor 4
A and B, or C and D is met at least 100 times:
A.
The pulse type of current injection is "ballistic".
B.
The total calculated injection time correction is more than 80 µseconds.
C.
The pulse type of current injection is "full-lift".
D.
The total calculated injection time correction is more than 200 µseconds.
Monitor 5
The measured "full-lift" closing time is less than 200 µseconds at least 100 times.
Monitor 7
The total calculated injection time correction after the controller is stable during the base adaptation for at least -50 µseconds.

Possible Cause
NOTE: The causes shown may not be a complete list of all potential problems, and it is possible that there may be other causes.
Improper fuel injection amount control operation
Poor connection of injector
Injector failure
Improper cylinder compression
Cylinder injection pipe collapsed
PCM internal circuit failure

Diagnosis Details
Conditions for setting the DTC
When a malfunction is detected during the first drive cycle, a Pending DTC is stored in the PCM memory. If the malfunction returns in the next (second) drive cycle, the MIL comes on and a Confirmed DTC and the freeze data are stored.

Conditions for clearing the DTC
The MIL is cleared if the malfunction does not return in three consecutive trips in which the diagnostic runs. The MIL, the Pending DTC, the Confirmed DTC, and the freeze data can be cleared with the scan tool Clear command.