19361-ZY3-000ZA Honda COVER, R. WATER JACKET *NH8* (Honda Code 6991087). (DARK GRAY)

Table 1
Diagnostic Trouble Codes for the DEF Pump Pressure Sensor
J1939 Code Code Description Comments
4334-3 Aftertreatment 1 Diesel Exhaust Fluid Doser 1 Absolute Pressure : Voltage Above Normal There is excessive voltage on the signal wire between the Electronic Control Module (ECM) and the DEF pump.
or
There is an open circuit on the supply, signal, or return wire.
The code is logged.
4334-4 Aftertreatment 1 Diesel Exhaust Fluid Doser 1 Absolute Pressure : Voltage Below Normal There is low voltage on the signal wire between the DCU and the DEF pump pressure sensor.
The code is logged.
Follow the troubleshooting procedure to identify the root cause of the problem.
Table 2
Required Tools
Tool Part Number Part Description Qty
A T4000242 Break-out Connector 1
Illustration 1 g06334650Note: All connectors may not be shown. Refer to the Electrical Schematic for the application for details of any connectors between the DEF pump connector and the ECM connectors.
Illustration 2 g03811015
Pin location on the DEF pump connector
(8) Return
(9) 12V supply
(10) PWM signalComplete the procedure in the order in which the steps are listed.
Table 3
Troubleshooting Test Steps Values Results
1. Inspect Electrical Connectors and Wiring
A. Inspect the connector for the DEF pump.
B. Thoroughly inspect any connectors between the DEF pump and the ECM. Refer to Troubleshooting, "Electrical Connectors - Inspect" for details.
C. Perform a 30 N (6.7 lb) pull test on each of the wires in the DEF pump connector and any connectors between the DEF pump and the ECM.
D. Check all the wiring associated with the DEF pump for abrasions and pinch points.
Note: Do not disconnect the ECM connector at this stage. The ECM can only be disconnected and reconnected 10 times before damage to the harness connector may occur.
Damaged wire or connector
Result: A damaged wire or damaged connector was not found.
Proceed to Test Step 2.
Result: A damaged wire or damaged connector was found.
Repair: Repair the damaged wire or the damaged connector.
Use the electronic service tool to clear all logged diagnostic codes. Verify that the repair eliminates the fault.
2. Check the 5V Supply to the DEF Pump Pressure Sensor
A. Turn the keyswitch to the OFF position.
B. Disconnect the connector for the DEF pump.
C. Turn the keyswitch to the ON position.
D. Use a suitable multimeter to measure the voltage between terminal 2 and terminal 4 on the harness connector for the DEF pump.
Between 4.84V and 5.16V
Result: The voltage measurement is not within the expected range.
If an interface connector is installed between the DEF pump and the ECM, proceed to Test Step 3.
If no interface connector is installed between the DEF pump and the ECM, the fault is in the ground or 5V supply wiring to the DEF pump.
Repair the faulty wiring or replace the faulty wiring. Use the electronic service tool to perform the "DEF Dosing System Verification Test" to check that the repair eliminates the fault.
Result: The voltage measurement is within the expected range.
Proceed to Test Step 4.
3. Check the 5V Supply to the Interface Connector
Note: This step is only applicable if an interface connector is installed between the DEF pump and the ECM. Refer to the Electrical Schematic for the application for more information. Proceed to Test Step 6 if no interface connector is installed.
A. Turn the keyswitch to the OFF position.
B. Disconnect the interface connector.
C. Use a suitable multimeter to measure the voltage between the sensor supply terminal and the sensor ground terminal on the interface connector.
Between 4.84V and 5.16V
Result: The voltage measurement is not within the expected range.
Repair: The fault is in the 5V supply wiring or the ground wiring between the interface connector and the ECM.
Repair the faulty wiring or replace the faulty wiring. Use the electronic service tool to perform the "DEF Dosing System Verification Test" to check that the repair eliminates the fault.
Result: The voltage measurement is within the expected range.
Proceed to Test Step 4.
4. Determine the Diagnostic Code
A. Establish communication between the electronic service tool and the engine Electronic Control Module (ECM). Refer to Troubleshooting, "Electronic Service Tools"
B. Check for active or logged codes.
Diagnostic trouble codes
Result: There is an active logged 4334-4 diagnostic code.
Proceed to Test Step 5.
Result: There is an active 4334-3 diagnostic code.
Proceed to Test Step 8.
5. Create an Open Circuit at the DEF Pump Connector
A. Turn the keyswitch to the OFF position.
B. Disconnect the DEF pump harness connector.
C. Turn the keyswitch to the ON position. Wait at least 30 seconds for activation of the diagnostic codes.
D. Use the electronic service tool to check for an active 4334-3 diagnostic code.
Diagnostic codes
Result: A 4334-4 diagnostic code was active before disconnecting the DEF pump. A 4334-3 diagnostic code became active after disconnecting the DEF pump.
Repair: The fault is in the DEF pump pressure sensor.
Install a replacement DEF pump. Use the electronic service tool to perform the "DEF Dosing System Verification Test" to check that the repair eliminates the fault.
Result: The 4334–4 diagnostic code is still active.
Proceed to Test Step 6.
6. Create an Open Circuit at the Interface Connector (if equipped
Note: This step is only applicable if an interface connector is installed between the DEF pump and the ECM. Refer to the Electrical Schematic for the application for more information. Proceed to Test Step 7 if no interface connector is installed.
A. Turn the keyswitch to the OFF position.
B. Disconnect the interface connector between the DEF pump and the ECM.
C. Turn the keyswitch to the ON position. Use the electronic service tool to start the "DEF Dosing System Verification Test". This test will command the DEF pump on.
D. Check for active diagnostic codes.
Greater than 1k Ohm
Result: A 4334-4 diagnostic code was active before disconnecting the interface connector. A 4334-3 diagnostic code became active after disconnecting the interface connector.
Repair: The fault is in the wiring between the interface connector and the DEF pump connector.
Repair the faulty wiring or replace the faulty wiring. Use the electronic service tool to perform the "DEF Dosing System Verification Test" to check that the repair eliminates the fault.
Result: The 4334–4 diagnostic code is still active.
Proceed to Test Step 7.
7. Check the Wiring to the ECM for a Short Circuit
A. Turn the keyswitch to the O