866565T Mercruiser PUMP/MOTOR ASSEMBLY, Trim - 12 Volt

The ARD nozzle can become plugged with carbon or with debris. The engine is equipped with a system that cleans the nozzle. The ECM periodically tests the condition of the nozzle. The ARD combustion head contains an electric heating element. The heating element operates periodically to clean the nozzle.ARD Nozzle Heater Circuit TestThe electronic service tool includes the "ARD Nozzle Heater Circuit Test". This override will assist the analysis of the ARD nozzle heater circuit. The override can be used to control the operation of the ARD nozzle heater while the engine is not running.
Illustration 1 g06144465
Schematic for the ARD nozzle heater
Illustration 2 g02041053
Pin locations on the P2 connector for the ARD nozzle heater
(41) ARD nozzle heater relay return
(43) ARD nozzle heater relay control
Illustration 3 g02169813
Pin locations on the 31-pin connector and the 40-pin connector for the ARD nozzle heater circuit
Illustration 4 g06144481
Typical example of a control panel for the Clean Emissions Module (CEM)
(1) Relay for the ARD nozzle heater
(2) Connector for the ARD nozzle heater relay (hidden)
(3) 2-pin connector for the ARD nozzle heater
Do not energize the heater for more than 30 seconds. If the heater is energized more than 30 seconds, damage to the heater can occur. Allow the heating element to cool for 2 minutes between power cycles.
Complete the procedure in the order in which the steps are listed.
Table 2
Troubleshooting Test Steps Values Results
1. Inspect Electrical Connectors and Wiring
A. Check that the fuses are not blown.
B. Inspect the connectors for the ARD heater and the ARD heater relay. Refer to Troubleshooting, "Electrical Connectors - Inspect" for details.
C. Inspect the 31-pin connector and the 40-pin connector. Refer to Troubleshooting, "Electrical Connectors - Inspect".
D. Perform a 45 N (10 lb) pull test on each of the wires in the ECM connector that are associated with the aftertreatment identification module.
E. Check the screw for the ECM connector for the correct torque of 6 N m (53 lb in).
F. Check the harness for abrasion and pinch points from the ARD nozzle heater back to the ECM.
Connectors and wiring
Result: There is a fault with the harness or the connectors.
Repair: Repair the connectors or the harness and/or replace the connectors or the harness. Ensure that all the seals are correctly in place and ensure that the connectors are correctly connected. Replace blown fuses.
Start the engine. Wait for the engine to reach operating temperature.
Use the "ARD Nozzle Heater Circuit Test" in the electronic service tool to switch on the ARD nozzle heater. Check for active diagnostic codes.
Confirm that the fault has been eliminated.
Note: If a fuse is replaced and the fault reoccurs, continue with this procedure.
Result: All connectors, pins, and sockets are correctly coupled and/or inserted. The harness is free of corrosion, abrasion, and pinch points. The fuses are not blown.
Proceed to Test Step 2.
2. Check for Diagnostic Codes
A. Connect the electronic service tool to the diagnostic connector.
B. Turn the keyswitch to the ON position.
C. Download the following items before performing any troubleshooting or clearing any diagnostic codes:
Warranty Report
Aftertreatment Regeneration Trigger History
Product Status Report with Histograms
D. Start the engine. Wait for the engine to reach operating temperature.
E. Check for an active 4301-5 (3182-5) diagnostic code.
F. Use the "ARD Nozzle Heater Circuit Test" in the electronic service tool to switch on the ARD nozzle heater. Check for an active 4301-6 (3182-6) diagnostic code.
G. Use the "ARD Nozzle Heater Circuit Test" in the electronic service tool to switch off the ARD nozzle heater.
Diagnostic codes
Result: A 4301-5 (3182-5) diagnostic code is active or recently logged.
Proceed to Test Step 3.
Result: A 4301-6 diagnostic code is active or recently logged.
Proceed to Test Step 6.
Result: There are no active 4301 diagnostic codes. There may be a fault with the switched power circuit for the ARD nozzle heater. The ECM does not monitor the status of this condition.
Proceed to Test Step 10.
3. Create a Short Circuit at the ARD Nozzle Heater Relay
A. Turn the keyswitch to the OFF position.
B. Disconnect the connector for the ARD nozzle heater relay.
C. Fabricate a jumper wire that is 150 mm (6 inch) long.
D. Use the jumper to connect terminal 1 to terminal 4 on the harness connector for the relay.
E. Start the engine. Wait for the engine to reach operating temperature.
F. Check for an active 4301-5 (3182-5) diagnostic code.
G. Use the "ARD Nozzle Heater Circuit Test" in the electronic service tool to switch on the ARD nozzle heater. Check for an active 4301-6 (3182-6) diagnostic code.
H. Use the "ARD Nozzle Heater Circuit Test" in the electronic service tool to switch off the ARD nozzle heater.
I. Remove the jumper.
Short circuit
Result: A 4301-6 (3182-6) diagnostic code is active with the ju