19748 1 Mercury CLAMP, LOWER

Table 1
CDL Code J1939 Code Description
(code descriptions may vary) Comments
2489-5 3487-5 ARD Air Pressure Control Actuator : Current Below Normal There is low current flow in the wiring between the combustion air valve and the combustion air valve controller. Regenerations are disabled. The code is logged. Engine power is derated.
2489-6 3487-6 ARD Air Pressure Control Actuator : Current Above Normal There is excessive current flow in the wiring between the combustion air valve and the combustion air valve controller. Regenerations are disabled. The code is logged. Engine power is derated.
2489-7 3487-7 ARD Air Pressure Control Actuator : Not Responding Properly The combustion air valve is not responding properly to commands from the combustion air valve controller. The code is logged. Engine power is derated.
2489-8 3487-8 ARD Air Pressure Control Actuator : Abnormal Frequency, Pulse Width, or Period The combustion air valve is not responding properly to commands from the combustion air valve controller. The code is logged. Engine power is derated.
2490-3 3488-3 ARD Air Pressure Control Actuator Position Sensor : Voltage Above Normal There is excessive voltage on the signal wire between the combustion air valve and the combustion air valve controller. The code is logged. Engine power is derated.
2490-4 3488-4 ARD Air Pressure Control Actuator Position Sensor : Voltage Below Normal There is low voltage on the signal wire between the combustion air valve and the combustion air valve controller. The code is logged. Engine power is derated.
3471-5 5591-5 ARD Air Pressure Control Module : Current Below Normal There is low current flow in the wiring between the engine ECM and the combustion air valve controller. The code is logged.
3471-6 5591-6 ARD Air Pressure Control Module : Current Above Normal There is excessive current flow in the wiring between the engine ECM and the combustion air valve controller. The code is logged.
3472-3 5591-3 ARD Air Pressure Control System : Voltage Above Normal There is excessive voltage on the voltage supply wire to the combustion air valve controller. The code is logged. Engine power is derated.
3472-4 5591-4 ARD Air Pressure Control System : Voltage Below Normal There is low voltage on the voltage supply wire to the combustion air valve controller. The code is logged. Engine power is derated.
3472-9 5591-9 ARD Air Pressure Control System : Abnormal Update Rate There is no communication between the engine ECM and the combustion air valve controller. The code is logged. Engine power is derated.
3482-3 3511-3 Sensor Supply #3 : Voltage Above Normal There is excessive voltage on the 5 VDC wire between the combustion air valve and the combustion air valve controller. The code is logged. Engine power is derated.
3482-4 3511-4 Sensor Supply #3 : Voltage Below Normal There is low voltage on the 5 VDC wire between the combustion air valve and the combustion air valve controller. The code is logged. Engine power is derated. System OperationThe combustion air system consists of the following components:
Combustion air valve controller
Combustion air valve
Combustion air absolute pressure sensorCombustion Air Valve Controller (A5M8)The combustion air valve controller receives operating voltage from the control system. The controller receives commands from the ECM for the engine via a CAN data link. The controller converts the commands from the ECM into a command signal for the combustion air valve. The controller also provides 5 VDC to the valve position sensor.Combustion Air ValveThe combustion air valve positions an actuator according to the commands from the controller. The position sensor sends a signal to the controller. The signal indicates the position of the actuator.The combustion air valve controller sends the position of the actuator to the engine ECM via the CAN data link. The position of the actuator can be viewed on Caterpillar Electronic Technician (ET). The controller also sends diagnostic information to the ECM.Absolute Pressure SensorThe combustion air absolute pressure sensor converts the absolute pressure of the combustion air into an electrical signal. The ECM uses the signal to determine the volume of combustion air that is being provided to the ARD. The ECM changes the command to the combustion air controller until the volume of combustion air is correct.
Table 2
Troubleshooting Test Steps Values Results
1. Determine the Diagnostic Code
A. Establish communication between Cat ET and the ECM . Refer to Troubleshooting, "Electronic Service Tools", if necessary.
B. Record the logged codes or the active codes.
Diagnostic Code
Result: A 3487-5, 3487-6, 3488-3, 3488-4, 3511-3 or a 3511-4 code is logged or active. There is a problem with the wiring between the combustion air valve controller (A5M8) and the combustion air valve.
Proceed to Test Step 7.
Result: A 2489-5, 2489-6, 2490-3, 2490-4, 3482-3 or a 3482-4 code is logged or active. There is a problem with the wiring between the combustion air valve controller (A5M8) and the combustion air valve.
Proceed to Test Step 7.
Result: A 5591-3 or a 5591-4 code is logged or active. There is a problem with the power supply to the combustion air controller (A5M8).
Proceed to Test Step 8.
Result: A 3472-3, 3472-4, 3471-5 or a 3471-6 code is logged or active. There is a problem with the power supply to the combustion air controller (A5M8).
Proceed to Test Step 8.
Result: A 3472-9 or a 5591-9 code is logged or active. There is a problem with the data link wiring between the engine ECM and the combustion air valve controller (A5M8).
Proceed to Test Step 9.
Result: A 2489-7 or a 3487-7 code is logged or active.
Proceed to Test Step 2.
Result: A 2489-8 or a 3487-8 code is logged or active.
Clear all logged or active codes and Proceed to Test Step 6.
Result: There are not any diagnostic codes present.
Proceed to Test Step 3.
Illustration 1 g02728374
Typical example