Exhaust Particulate Filter Cleaning
Diagnostic Instructions
Circuit/System Description
If a vehicle has an active or inactive diesel particulate filter
(DPF) related diagnostic trouble code (DTC) a scan tool can be used
to initiate a controlled service mode DPF regeneration. This
function assists in locating the DPF components requiring repair.
The service regeneration mode is also the only way to regenerate
the DPF when the soot mass level has increased past the maximum
threshold. When the DPF soot mass level exceeds a calibrated value,
the ECM will command power reduction and normal driving
regeneration is inhibited. Performing a service regeneration will
remove the power reduction command. The service regeneration mode
ignores many of the abort conditions required for normal driving
regeneration. The service regeneration mode is also useful to
verify that repairs to the DPF system have been successful. DPF
diagnostics are active during a service regeneration. Monitoring
for DPF DTCs during the service regeneration will help determine if
any issues are present. If any DTCs occur, repair the issue and
rerun the service regeneration mode. During the service
regeneration procedure, the tailpipe outlet temperature will be
greater than 550°C (1,022°F). Use caution around the engine
compartment, and exhaust system during the regeneration
procedure.
Reference Information
Scan Tool Reference
Control Module References for scan tool information
Circuit/System Verification
| 1. |
Ignition OFF, verify the
coolant is at the correct level. |
| ⇒ |
If the coolant is low, refer to
Loss of Coolant for diagnosis of the cooling system. |
| 2. |
Ignition ON, observe the scan
tool diagnostic trouble code (DTC) information. Verify there are no
DTCs set. |
| 3. |
Engine idling, verify there
are no engine mechanical conditions. |
| 4. |
Observe the scan tool DPF soot
mass parameter. The parameter should be less than 5 grams.
|
Circuit/System Testing
|
Warning:
Tailpipe outlet exhaust temperatures will be
greater than 550°C (1022°F) during service regeneration. In
order to prevent personal injury or property damage from fire, or
burns, perform the following:
| |
|
• |
Inspect and remove any debris from the
exhaust system prior to service regeneration. |
| |
|
• |
Do not connect any shop exhaust removal hoses
to the vehicle tailpipe. |
| |
|
• |
Park the vehicle outdoors with the hood open,
away from walls or buildings. |
| |
|
• |
Keep people, other vehicles, and combustible
material away during service regeneration. |
| |
|
• |
Do not leave the vehicle unattended.
|
|
Note:
| • |
The service
regeneration procedure can be stopped at any time in an emergency
by switching off the ignition, depressing the brake pedal, or with
a scan tool. Depressing the brake pedal returns the engine to idle
speed. The scan tool function allows the engine to slowly return to
idle. |
| • |
Oil changes may be
necessary after running the service regeneration mode. Every time
the service regeneration is run, the oil viscosity will be reduced.
Change the engine oil after service regeneration if the oil life
remaining is less than 80%. Also, if more than 3 service
regenerations are run consecutively, change the engine oil
regardless of the oil life remaining. |
| 1. |
Inspect the DPF. Verify there
is no soot leaking from the DPF. |
| ⇒ |
If soot is present, replace the DPF. |
| 2. |
Select the DPF service
regeneration in the scan tool output control menu. |
| 3. |
Follow the corresponding
instructions displayed on the screen of the scan tool. |
| 4. |
After completing the DPF
service regeneration, operate the engine at 1 500 RPM for 1 minute
in order to let the exhaust cool evenly. |
| 5. |
Ignition OFF, allow the engine
to cool down. |
| 6. |
Verify the coolant is at the
correct level. |
Repair Instructions
Exhaust Particulate Filter Replacement
Repair Verification
| • |
Ignition ON, observe the scan
tool diagnostic trouble code (DTC) information. Verify there are no
DTCs set. |
| • |
Engine idling, verify the scan
tool DPF soot mass parameter is near 0 grams. |
| ⇒ |
If not within the specified range, repeat the
service regeneration procedure. |
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