P20E892

DTC (Code)
Codigo:
Bulletin:
P20E8-92
RD18-002
Date Fecha: July 2, 2018
Description:
Reductant Pressure Too Low - Performance or incorrect
operation
Application:
US13 – US20 Emissions
General Information
These repair instructions are intended to address the following fault(s):
DTC
Description
•
•
•
P20E8-92
Reductant
Pressure Too
Low Performance or
incorrect
operation
Possible (Observable)
Symptoms
Possible Cause
•
•
•
•
•
•
•
•
•
•
Empty tank
Frozen aftertreatment diesel exhaust fluid (DEF)
DEF Supply from Aftertreatment DEF Tank
disconnected
Aftertreatment DEF Line(s) Leakage
Aftertreatment DEF dosing valve Leakage
Aftertreatment Diesel Exhaust Fluid (DEF) Pump
Leakage
Damaged sending unit inside the aftertreatment
DEF tank
Damaged or clogged filter
Aftertreatment DEF Dosing Pressure Sensor,
Incorrect value
Blocked DEF tank ventilation hose
Air in the system
Crystallization inside the DEF pump
Low level in Placeholder
•
•
No aftertreatment
diesel exhaust fluid
(DEF) dosage
Engine de-rated
Required Parts
Part Number
Description
Quantity
21576178
Diesel Exhaust Fluid (DEF) Pump Unit
1
Repair Instructions
Aftertreatment Diesel Exhaust Fluid (DEF) Pump Unit, Replacement
© 2016 Information is subject to change without notice.
Page 1 of 4
DTC (Code)
Codigo:
P20E8-92
Bulletin:
RD18-002
Date Fecha: July 2, 2018
Before replacing the DEF Pump Unit please check for damaged return hoses and connectors.
•
Disconnect and clean the aftertreatment DEF lines between the DEF tank and the DEF pump using water and
compressed air. If the line is broken then it will have to be replaced.
Removal
1. Apply parking brake and place shift lever in neutral.
2. Open rear engine service doors.
3. Remove all cables from ground (negative) battery terminals to prevent personal injury from electrical shock and
prevent damage to electrical components.
4. Open right rear engine service door.
5. Connect the coolant extractor to the drain fitting at the bottom of the radiator and drain the coolant. Note: An
alternate method is to connect the coolant drain hose to the drain fitting and drain the coolant into a suitable
container. Special tools: 85112740, 9996049
6. Place a suitable container under the DEF tank to catch fluid that may drain from the pump. Note: Use protective
equipment and an approved suitable container. Dispose of DEF according to local regulations.
7. Mark the DEF lines before removal. Remove the DEF inlet, backflow and outlet lines from the pump. Place
protective caps on the DEF lines. Note: For information on the handling of DEF, refer to “General Safety
Practices”, Group 20. Note: If inlet and backflow lines are switched, the system will not start.
1. DEF Outlet Line
2. DEF Backflow Line
3. DEF Inlet Line
© 2016 Information is subject to change without notice.
Page 2 of 4
DTC (Code)
Codigo:
P20E8-92
Bulletin:
RD18-002
Date Fecha: July 2, 2018
8. Remove the inlet and outlet coolant lines from the pump. Place protective caps on the coolant lines.
1. Coolant Lines
9. Remove cable tie and disconnect the wiring harness connector from the DEF pump. Cover the wiring harness
connector with a plastic bag to protect from possible damage from DEF.
10. Remove the fasteners, brackets and DEF pump from the mounting bracket.
1. DEF Pump
2. Fasteners
3. Brackets
© 2016 Information is subject to change without notice.
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DTC (Code)
Codigo:
Bulletin:
P20E8-92
RD18-002
Date Fecha: July 2, 2018
Installation
1. Position the DEF pump onto the mounting bracket and install brackets and fasteners. Tighten the fasteners to
specification, refer to Function Group 20, Specifications.
2. Remove plastic bag from the wiring harness connector. Attach the wiring harness connector to the DEF pump
and secure the harness using a cable tie.
3. Install the inlet and outlet coolant lines onto the DEF pump.
4. Install DEF inlet, backflow and outlet lines onto the pump. Note: If inlet and backflow lines are switched, the
system will not start.
5. Fill the cooling system with the recommended coolant using the coolant extractor. Ensure the coolant system is
full. Special tools: 85112740
6. Install all previously removed cables to the ground (negative) battery terminals.
7. Connect Tech Tool to the vehicle. Use Guided Diagnostics to read and clear any diagnostic trouble codes
(DTCs). Check for proper operation and for leaks.
8. Close right rear engine service door.
9. Close rear engine service doors.
Additional Resources
These repairs are the most likely fix for the identified fault, if this does not fix the issue, Tech Tool will need to be used
for more detailed diagnostics. If filing a warranty claim, please include the ASIST case number.
Labor Code
2589-03-02-36
1.2
Causal Part
21576178
© 2016 Information is subject to change without notice.
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