TRANSMISSION OVERHAUL 5P3764 - Caterpillar

System Operation Description:This procedure covers the following codes:
Table 1
Diagnostic Trouble Codes for the Valve Position Sensors    
J1939 Code    Description    Notes    
27-3     Engine Exhaust Gas Recirculation Valve Position : Voltage Above Normal     The Electronic Control Module (ECM) detects the following conditions:
The signal voltage from the position sensor on the NOx Reduction System (NRS) valve is greater than 4.8 VDC for 0.1 seconds.
If equipped, the warning lamp will come on. The ECM will log the diagnostic code. The NRS valve will be fully closed while the code is active.
The engine will be derated.    
27-4     Engine Exhaust Gas Recirculation Valve Position : Voltage Below Normal     The ECM detects the following conditions:
The signal voltage from the NRS valve position sensor is less than 0.2 VDC for 0.1 seconds.
If equipped, the warning lamp will come on. The ECM will log the diagnostic code. The NRS valve will be fully open while the code is active.
The engine will be derated.    
51-3     Engine Throttle Position : Voltage Above Normal     The ECM detects the following conditions:
The signal voltage from the position sensor on the engine intake throttle valve is greater than 4.8 VDC for 0.1 seconds.
If equipped, the warning lamp will come on. The ECM will log the diagnostic code. The engine intake throttle valve will be fully closed while the code is active.
The engine will be derated.    
51-4     Engine Throttle Position : Voltage Below Normal     The ECM detects the following conditions:
The signal voltage from the position sensor on the engine intake throttle valve is less than 0.2 VDC for 0.1 seconds.
If equipped, the warning lamp will come on. The ECM will log the diagnostic code. The engine intake throttle valve will be fully closed while the code is active.
The engine will be derated.    
3488-3     Aftertreatment #1 Air Pressure Actuator Position : Voltage Above Normal     The ECM detects the following conditions:
The signal voltage from the position sensor on the combustion air valve is greater than 4.85 VDC for 8 seconds.
If equipped, the warning lamp will come on. The ECM will log the diagnostic code.
The engine will be derated.    
3488-4     Aftertreatment #1 Air Pressure Actuator Position : Voltage Below Normal     The ECM detects the following conditions:
The signal voltage from the position sensor on the combustion air valve is less than 0.2 VDC for 8 seconds.
If equipped, the warning lamp will come on. The ECM will log the diagnostic code.
The engine will be derated.    The following conditions must exist before any of the preceding codes will become active:
The ECM has been powered for at least 2 seconds.
There are no active 3509 codes.
There are no active 168 codes.Use this procedure in order to troubleshoot the position sensors for the following valves:
NRS valve
Engine intake throttle valve
Combustion air valve for the Aftertreatment Regeneration Device (ARD)Each position sensor is integral in the associated valve. If the following procedure indicates a fault with the position sensor, then the entire valve must