IDLER GP-FRONT 8V2694 - Caterpillar

Illustration 1 g03713516
View of the DEF pump module
(1) DEF backflow line connector
(2) DEF pressure line connector
(3) DEF suction line connector
Illustration 2 g03713528
View of the DEF tank and DEF tank header unit
(4) DEF backflow line connector
(5) DEF suction line connector Complete the procedure in the order in which the steps are listed.
Table 2
Troubleshooting Test Steps Values Results
1. Check the Level in the DEF Tank
A. Check that there is sufficient DEF in the DEF tank.
Note: If there is insufficient DEF in the DEF tank, the system can fill with air.
DEF Level
Result: There is not enough DEF in the DEF tank.
Repair: Fill the DEF tank with DEF. Refer to Operation and Maintenance Manual, "Diesel Exhaust Fluid - Fill".
Result: The level in the DEF tank is OK.
Proceed to Test Step 2.
2. Check for Diagnostic Trouble Codes
A. Turn the keyswitch to the ON position. Do not start the engine.
B. Connect to the electronic service tool.
C. Check for active or recently logged diagnostic trouble codes.
Diagnostic trouble codes
Result: One of the diagnostic codes listed in Table 1 is active or recently logged.
Proceed to Test Step 3.
Result: A code other than 4334-7 is active or recently logged.
Repair: Troubleshoot the logged or active code. Refer to Troubleshooting, "Diagnostic Trouble Codes".
3. Check the DEF Line Heaters
A. Check that the DEF line heaters are working correctly.
Refer to Troubleshooting, "DEF Line Heater - Test".
DEF line heaters
Result: The DEF line heaters are not OK.
Repair: Make any necessary repairs. Refer to Troubleshooting, "DEF Line Heater - Test".
Start the engine. If the fault is still present, proceed to Test Step 4.
Result: The DEF line heaters are OK.
Proceed to Test Step 4.
4. Inspect the DEF Lines for Leaks
A. Turn the keyswitch to the ON position. Do not start the engine.
B. Ensure that the DEF lines are connected to the correct connectors on the DEF pump and the DEF tank header.
C. Remove the DEF injector from the SCR cannister.
D. Connect to the electronic service tool.
E. Use the electronic service tool to perform the "DEF Dosing System Verification Test".
F. Visually inspect all DEF lines. Look for pinched, damaged, or disconnected lines. Inspect the lines for leaks.
G. Inspect the DEF injector for signs of leakage.
H. Turn the keyswitch to the OFF position.
DEF Lines
Result: The DEF lines are not installed correctly.
Repair: Install the DEF lines to the correct connectors.
Use the electronic service tool to perform the "DEF Dosing System Verification Test" and check that the diagnostic code is no longer active.
Result: The lines are leaking, damaged, pinched, or disconnected.
Repair: Make the necessary repairs.
Result: The DEF lines are installed correctly.
Repair: Proceed to Test Step 5.
5. Check the DEF Lines for Obstructions
A. Remove the suction line from the DEF tank header (5) and DEF pump (3).
B. Remove the pressure line from the DEF injector and DEF pump (2).
C. Remove the backflow line from the DEF pump (1) and the DEF pump header (4).
D. Inspect the lines for obstructions. Flush lines with water/low pressure air if necessary.
Note: Possible obstructions are ice, DEF deposits, or debris.
E. Inspect the DEF tank filter and the DEF