P2002

P2002-DIESEL PARTICULATE FILTER EFFICIENCY BELOW THRESHOLD

For complete wiring diagrams refer to Diagrams/Electrical.


Theory of Operation

The aftertreatment diesel particulate filter is designed to physically filter soot and to eliminate hydrocarbons from the engine exhaust gases through catalyst reactions in the exhaust stream. Federal law requires that the filter's efficiency be monitored for signs of degradation that would compromise the efficiency of the filter. The ECM monitors the efficiency of the aftertreatment diesel particulate filter via interpretation of data received from the Exhaust Pressure Sensor, which monitors the restriction across the aftertreatment diesel particulate filter. The ECM monitors the restriction in the aftertreatment diesel particulate filter at various engine speeds/loads and will set the fault if the restriction is below a calibrated threshold minimum value. The ECM will illuminate the MIL light Immediately when the diagnostic runs and fails in two consecutive drive cycles. Active regeneration of the aftertreatment Diesel particulate filter will also be disabled for the remainder of the drive cycle. The ECM will try to regenerate the aftertreatment diesel particulate filter on the next subsequent drive cycle. The ECM will turn off the MIL light immediately after the diagnostic runs and passes in four consecutive drive cycles.

- When Monitored:

This diagnostic runs when the engine is running and after an active regeneration of the aftertreatment diesel particulate filter has completed.

- Set Condition:

The ECM will set the fault if the diagnostic fails in two consecutive drive cycles.







Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding.

Diagnostic Test


1. OTHER DTCS

Ignition on, engine not running.

With the scan tool, read DTCs.

Are any other DTCs Active?

Yes

- Repair all other DTCs first.

No

- Go To 2

2. EXHAUST LEAKS

Check the aftertreatment system for exhaust leaks.

Does the aftertreatment system leak?

Yes

- Repair the exhaust leaks.
- Perform POWERTRAIN VERIFICATION TEST. Powertrain Verification Test

No

- Go To 3

3. P2002 ACTIVE

Ignition on, engine not running.

With the scan tool, read DTCs.

Is DTC P2002 Active?

Yes

- Replace the aftertreatment diesel particulate filter.
- Perform POWERTRAIN VERIFICATION TEST. Powertrain Verification Test

No

- Go To 4

4. AFTERTREATMENT DIESEL PARTICULATE FILTER

Remove and inspect the aftertreatment diesel particulate filter.

Does aftertreatment diesel particulate filter show evidence of failure?

Yes

- Replace the aftertreatment diesel particulate filter.
- Perform POWERTRAIN VERIFICATION TEST. Powertrain Verification Test

No

- Refer to the INTERMITTENT CONDITION Diagnostic Procedure. Intermittent Condition