98789 Mercury SCREW,RETAINER TO HOUSING

Table 1
Diagnostic Trouble Codes for the Motorized Valves    
CDL Code    Description    Notes    
3405-5     EGR Valve Control : Current Below Normal     The ECM detects the following conditions:
A low current condition in the output for the NOx Reduction System (NRS) valve (EGR valve) for 2 seconds
168 diagnostic codes are not active.
The ECM has been powered for at least 2 seconds.
If equipped, the warning lamp will come on. The ECM will log the diagnostic code.    
3405-6     EGR Valve Control : Current Above Normal     The ECM detects the following conditions:
A high current condition in the output for the NRS valve (EGR valve) for 2 seconds
The ECM has been powered for at least 2 seconds.
If equipped, the warning lamp will come on. The ECM will log the diagnostic code.    
E1121-2     EGR Valve Control Not Responding to Command     The ECM detects the following conditions:
The signal from the NRS valve position sensor indicates that the valve is not in the desired position.
This diagnostic code can be caused by a loss of the 5 VDC supply to the NRS valve position sensor.
The ECM has been powered for at least 2 seconds.
If equipped, the warning lamp will come on. The ECM will log the diagnostic code.    
3514-5     Engine Throttle Actuator : Current Below Normal     The ECM detects the following conditions:
A low current condition in the output for the engine intake throttle valve for 2 seconds
168 diagnostic codes are not active.
The ECM has been powered for at least 2 seconds.
If equipped, the warning lamp will come on. The ECM will log the diagnostic code.    
3514-6     Engine Throttle Actuator : Current Above Normal     The ECM detects the following conditions:
A high current condition in the output for the engine intake throttle valve for 2 seconds
The ECM has been powered for at least 2 seconds.
If equipped, the warning lamp will come on. The ECM will log the diagnostic code.    
E1262-2     Engine Throttle Actuator Not Responding to Command     The ECM detects the following conditions:
The signal from the engine intake throttle valve position sensor indicates that the valve is not in the desired position.
This diagnostic code can be caused by a loss of the 5 VDC supply to the engine intake throttle valve position sensor.
The ECM has been powered for at least 2 seconds.
If equipped, the warning lamp will come on. The ECM will log the diagnostic code.    
2489-5     ARD Air Pressure Control Actuator : Current Below Normal     The ECM detects the following conditions:
A low current condition in the output for the combustion air valve for 2 seconds
The ECM has been powered for at least 2 seconds.
If equipped, the warning lamp will come on. The ECM will log the diagnostic code.    
2489-6     ARD Air Pressure Control Actuator : Current Above Normal     The ECM detects the following conditions:
A high current condition in the output for the combustion air valve for 2 seconds
The ECM has been powered for at least 2 seconds.
If equipped, the warning lamp will come on. The ECM will log the diagnostic code.    
E1041-2     ARD Air Pressure Control Actuator Not Responding to Command     The ECM detects the following conditions:
The signal from the combustion air valve position sensor indicates that the valve is not in the desired position.
This diagnostic code can be caused by a loss of the 5 VDC supply to the engine intake throttle valve position sensor.
The ECM has been powered for at least 2 seconds.
If equipped, the warning lamp will come on. The ECM will log the diagnostic code.    The following background information is related to this procedure:
ARD combustion air valveThe Aftertreatment Regeneration Device (ARD) increases the exhaust gas temperature in order to burn off the soot that is collected in the DPF. The ARD requires a supply of fuel and clean air. The air supply is regulated by the ARD combustion air valve.The amount of air that is required by the ARD is calculated by the software that is contained in the ECM. The combustion air valve is controlled by a PWM signal from the ECM.NRS valve (EGR valve) and engine intake throttle valveThe NRS valve (EGR valve) is used to control the amount of exhaust gas which is recirculated into the intake manifold.The amount of exhaust gas that is required is calculated by the software that is contained in the ECM.When necessary, the engine intake throttle valve reduces the intake manifold pressure so that the pressure in the NRS mixer is always higher. This pressure differential ensures that recirculated exhaust gases will flow into the intake manifold.The NRS valve and the engine intake throttle valve are controlled by a PWM signal from the ECM.
Illustration 1 g02364276
Schematic for the motorized valves
Illustration 2 g02009195
Typical view of the pin locations on the P2 connector for the motorized valves (1) Engine intake throttle valve return (2) Engine intake throttle valve signal (32) NRS valve return (40) NRS valve signal (45) Combustion air valve position sensor 5 VDC supply (46) NRS valve/intake throttle valve position sensor 5 VDC supply (55) Combustion air valve position sensor ground (56) NRS valve/intake throttle valve position sensor ground (48) Combustion air valve return (58) Combustion air valve signal
Illustration 3 g02315693
Typical example of the connector for the combustion air valve (1) Position sensor 5 VDC supply (2) Position sensor return (4) Combustion air valve ground (6) Combustion air valve signal
Illustration 4 g02315694
Typical example of the connector for the engine intake throttle valve (1) Engine intake throttle valve supply (2) Engine intake throttle valve return (3) Position sensor ground (5) Position sensor 5 VDC supply
Illustration 5 g02315757
Typical example of the connector for the NRS valve (1) Position sensor 5 VDC supply (2) Position sensor ground (4) NRS valve return (6) NRS valve signalTest Step 1. Inspect Electrical Connectors and Wiring
Thoroughly inspect connectors for the motorized valves. Refer to Troubleshooting, "Electrical Connectors - Inspect" for details.
Thoroughly inspect the 31-pin connector and the 40-pin connector. Refer to Troubleshooting, "Electrical Connectors - Inspect" for details.
Perform a