5033559 JOHNSON HOUSING - 25 in.

Table 2
Troubleshooting Test Steps Values Results
1. Check the Diesel Exhaust Fluid (DEF) tank filler cap
A. Clean dirt and debris from around the tank cap before removing the cap. Blockages can be caused by a build-up of dirt and debris around the cap.
Note : A blocked DEF filler cap can cause a 5392-31 or E1370 (2) code.
B. Remove and inspect the filler cap for blockages.
DEF filler cap
Result : A blockage was not found.
Proceed to Test Step 2.
Result : A blockage was found.
Repair : Rinse the cap gently with clean water or replace the cap.
Note: The cap contains a membrane so care must be taken not to damage the membrane. If the cap cannot be cleaned, the cap must be replaced.
Proceed to Test Step 2.
2. Check the Diesel Exhaust Fluid (DEF) Gauge
A. Turn the keyswitch to the ON position. Do not start the engine.
B. Check the current position of the DEF gauge.
C. Turn the keyswitch to the OFF position.
D. Clean dirt and debris from around the tank cap before removing the cap. Add or remove DEF from the DEF tank.
Note : Only use DEF that meets ISO 22241 quality standards.
E. Turn the keyswitch to the ON position. Do not start the engine.
F. Check for a change in the DEF gauge position.
DEF gauge
Result : The gauge did not move by adding or removing DEF from the tank.
Proceed to Test Step 3.
Result : The gauge moved by adding or removing DEF from the tank.
Proceed to Test Step 4.
3. Check the Electrical Connection at the DEF Tank Header
A. Turn the keyswitch to the OFF position.
B. Inspect the electrical connections to the DEF tank header. Refer to Troubleshooting, "Electrical Connectors - Inspect" for further information.
C. Inspect the connections for corrosion or loose wires.
Electrical connections
Result : The electrical connections are free of corrosion and loose wires.
Repair : Replace the DEF tank header. Refer to the Disassembly and Assembly manual for the correct procedure.
Proceed to Test Step 11.
Result : The electrical connections are not free of corrosion or loose wires.
Repair : Make the necessary repairs.
Proceed to Test Step 11.
4. Inspect the DEF Lines for Leaks
A. Turn the keyswitch to the ON position. Do not start the engine.
B. Connect to the "Aftertreatment Diesel Exhaust Fluid Controller #1" using the electronic service tool.
C. Navigate to "Diagnostics Tests".
D. Perform the "DEF Dosing System Verification Test" to pressurize the system.
Note: This test may take up to 30 minutes to complete.
E. Inspect all DEF lines from the tank to the DEF injector. Check for pinched, damaged, disconnected, or leaking lines.
F. Turn the keyswitch to the OFF position.
DEF lines
Result: A leaking or disconnected line was found.
Repair : Repair or replace the failed DEF line.
Proceed to Test Step 11.
Result: A leaking or disconnected line was not found.
Proceed to Test Step 5.
Illustration 1 g03337472
(1) DEF suction line connection on the header unit
Table 3
Troubleshooting Test Steps Values Results
5. Check the Diesel Exhaust Fluid (DEF) Quality
A. Measure the DEF quality. Refer to Testing and Adjusting, "Diesel Exhaust Fluid Quality - Test" for the correct procedure.
DEF
Result : The DEF is not contaminated.
Proceed to Test Step 6.
Result : The DEF is contaminated.
Repair : Contact the Dealer Solutions Network (DSN) for further information.
6. Check for Suction Line Restrictions
A. Disconnect the suction line from the DEF tank header and DEF pump.
B. Inspect the suction line for obstructions or damage. Also, check that the line is connected in the proper locations.
Note : Possible obstructions are ice, DEF deposits, or debris.
Restrictions
Result: An obstruction or damage was found.
Repair : Flush the line with water or low-pressure air or replace the suction line.
Proceed to Test Step 11.
Result: An obstruction or damage was not found.
Repair : Reinstall the suction line.
Proceed to Test Step 7.
Illustration 2 g03763616
(2) DEF suction line filter fitting
(3) DEF pump
(4) DEF pump filter cap
Table 4
Troubleshooting Test Steps Values Results
7. Check for Return Line Restrictions
A. Disconnect the return line from the DEF manifold and DEF pump.
B. Inspect the return line and return line fitting for obstructions or damage. Also, check that the line is connected in the proper locations.
Note : Possible obstructions are ice, DEF deposits, or debris.
Restrictions
Result: An obstruction or damage was found.
Repair : Flush the line or connector with water or low-pressure air or replace the return line or return line fitting.
Proceed to Test Step 11.
Result: An obstruction or damage was not found.
Repair : Reinstall the return line.
Proceed to Test Step 8.
8. Check for Manifold Leaks
A. Turn the keyswitch to OFF.
B. Remove the DEF manifold from the DEF tank.
C. Inspect the suction pipe on the manifold f