Customer Drive Cycle For Profile Correction (60-40 Mph Deceleration)
This method was the traditional method for profile correction learning until the introduction of Neutral Profile Correction. It is now only used as a backup method
To prevent any fueling or combustion differences from affecting the correction factors, learning is done during deceleration fuel shut off (DFSO). This can be done during closed throttle, non-braking, defueled decelerations in the 97 to 64 km/h (60 to 40 MPH) range after exceeding 97 km/h (60 MPH) (likely to correspond to a freeway exit condition). In order to minimize the learning time for the correction factors, a more aggressive DFSO strategy may be used when the conditions for learning are present. The corrections are typically learned in a single 97 to 64 km/h (60 to 40 MPH) deceleration, but may take up to 3 such decelerations or a higher number of shorter decelerations. If the software is unable to learn a profile after three, 97 to 64 km/h (60 to 40 MPH) deceleration cycles, DTC P0315 is set.
| DTCs | P0300 to P0310 (general and specific cylinder misfire) P1336 (noisy crank sensor, no cam/crank synchronization) P0315 (unable to learn profile) P0316 (misfire during first 1, 000 revs after start-up) P0313 (misfire detected with low fuel level) |
| Monitor execution | Continuous, misfire rate calculated every 200 or 1000 revs |
| Monitor Sequence | None |
| Sensors OK | CKP, CMP, MAF, ECT/CHT |
| Monitoring Duration | Entire driving cycle (see disablement conditions below) |
| Entry Condition | Minimum | Maximum |
| Time since engine start-up | 0 seconds | 0 seconds |
| Engine Coolant Temperature | 20 °F | 250 °F |
| RPM Range (Full-Range Misfire certified, with 2 rev delay) | 2 revs after exceeding 150 rpm below "drive" idle rpm | redline on tach or fuel cutoff |
| Profile correction factors learned in NVRAM | Yes | |
| Fuel tank level | 15% |
| Temporary disablement conditions: |
| Closed throttle decel (negative torque, engine being driven) > -100 ft lbs |
| Fuel shut-off due to vehicle-speed limiting or engine-rpm limiting mode |
| High rate of change of torque (heavy throttle tip-in or tip out) > -450 deg/sec or 250 deg/sec ; > -200 ft lbs/sec or > 250 ft lbs/sec |
| Rough Road conditions present |
| Type A (catalyst damaging misfire rate): misfire rate is an rpm/load table ranging from 40% at idle to 4% at high rpm and loads |
| Type B (emission threshold rate): 0.9% to 1.5% |
| Monitor ID | Test ID | Description | |
| A1 | $80 | Total engine misfire and catalyst damage misfire rate (updated every 200 revolutions) (P030x) | percent |
| A1 | $81 | Total engine misfire and emission threshold misfire rate (updated every 1, 000 revolutions) (P030x) | percent |
| A1 | $82 | Highest catalyst-damage misfire and catalyst damage threshold misfire rate (updated when DTC set or clears) (P030x) | percent |
| A1 | $83 | Highest emission-threshold misfire and emission threshold misfire rate (updated when DTC set or clears) (P030x) | percent |
| A1 | $84 | Inferred catalyst mid-bed temperature (P030x) | °C |
| A2 - AD | $0B | EWMA misfire counts for last 10 driving cycles (P030x) | events |
| A2 - AD | $0C | Misfire counts for last/current driving cycle (P030x) | events |
| A2 - AD | $80 | Cylinder X misfire rate and catalyst damage misfire rate (updated every 200 revolutions) (P030x) | percent |
| A2 - AD | $81 | Cylinder X misfire rate and emission threshold misfire rate (updated every 1, 000 revolutions) (P030x) | percent |
The profile learning operation includes DTC P0315 if profile correction factors are not learned. On selected vehicles, this code is set immediately after a new PCM is installed until the scan tool procedure for Neutral Profile Correction is completed. On all other vehicles, this code is set if profile learning does not complete during the Customer Drive Cycle for Profile Correction.
| DTCs | P0315 - unable to learn profile in three 60 to 40 mph decels |
| Monitor Execution | Once per profile learning sequence. |
| Monitor Sequence | Profile must be learned before misfire monitor is active. |
| Sensors OK | CKP, CMP, CKP/CMP in synch |
| Monitoring Duration | 10 cumulative seconds in conditions (a maximum of three 60-40 mph defueled decels) |
| Entry Condition | Minimum | Maximum |
| Engine in decel-fuel cutout mode for 4 engine cycles | ||
| Brakes applied (Brake On/Off Switch) | No | No |
| Engine RPM | 1300 rpm | 3700 rpm |
| Change in RPM | 600 rpm/background loop | |
| Vehicle Speed | 30 mph | 75 mph |
| Learning tolerance | 1% |
| Entry Condition | Minimum | Maximum |
| Engine in decel-fuel cutout mode for 4 engine cycles | ||
| Park/Neutral gear | ||
| Engine RPM | 2000 rpm | 3000 rpm |
| Learning tolerance | 1% |