0307384 JOHNSON SPRING, Choke throttle

Table 1
Diagnostic Codes
CDL Code Code Description Comments
41-3 8 Volt DC Supply : Voltage Above Normal The code is logged.
The digital sensor is set to the default value.
41-4 8 Volt DC Supply : Voltage Below Normal
262-3 5 Volt Sensor DC Power Supply : Voltage Above Normal The code is logged.
All sensors are set to default values.
262-4 5 Volt Sensor DC Power Supply : Voltage Below Normal
460-21 Fuel Pressure Sensor - After Fuel Filter : Data Drifted Low The code is logged.
The sensor is set to the default value.
1785-10 Intake Manifold Pressure Sensor : Abnormal Rate of Change The code is logged.
The sensor is set to the default value.
1785-21 Intake Manifold Pressure Sensor : Data Drifted Low The code is logged.
The sensor is set to the default value.
2131-3 5 Volt Sensor DC Power Supply #2 : Voltage Above Normal The code is logged.
Engine power may be derated.
2131-4 5 Volt Sensor DC Power Supply #2 : Voltage Below Normal
3385-21 EGR Intake Pressure Sensor : Data Drifted Low The code is logged.
The sensor is set to the default value. System OperationThe Electronic Control Module (ECM) supplies a regulated voltage of 5.0 0.2 VDC to the following sensors:
Aftertreatment ID module
Atmospheric pressure sensor
Buffer for the exhaust temperature sensors (left side)
Buffer for the exhaust temperature sensors (right side)
Crankcase pressure sensor
Engine oil pressure sensor
Fuel pressure sensor (filtered fuel pressure)
Intake manifold pressure sensor
NRS absolute pressure sensor
NRS differential pressure sensor
Turbocharger inlet pressure sensor (left side)
Turbocharger inlet pressure sensor (right side)The ECM supplies a regulated voltage of 8.0 0.4 VDC to the following sensor:
Throttle position sensorThe supply voltage for the sensors is routed from the ECM to terminal 1 of each sensor connector. The sensor return for the sensors is routed from the ECM to terminal 2 of each sensor connector.-10 Code - The engine must be running in order for this code to become active. During normal engine operation, the actual system pressures will fluctuate slightly. If the fluctuation for the signal slows or the fluctuation of the signal stops, the -10 code will be activated. The failure modes for this code include a problem in the circuit for the sensor supply. The failure modes also include an internal electrical problem with the sensor, or a problem in the circuit for the sensor signal. If the signal from the pressure sensor remains abnormally steady for more than 30 seconds, the ECM activates this code. A snapshot is triggered. The ECM sets the value of the suspect sensor to the default value.-21 Code - This code becomes active when the ECM determines that the 5 v supply is missing at the pressure sensor. The ECM sets the value of the suspect sensor to the default value.The ECM provides short circuit protection for the internal power supply. A short circuit to the battery will not damage the internal power supply.Note: The sensors are not protected from overvoltage. A short from the supply line to the +Battery may damage the sensors. If any of the three diagnostic codes are active, a sensor may have been damaged. Repair the sensor supply and check for any active sensor diagnostic codes in order to determine if a sensor has been damaged.
Illustration 1 g02131633
Schematic of the circuits for the analog sensor supplies
Illustration 2 g02137674
Schematic of the circuits for the digital sensor supply
Test Step 1. Inspect the Electrical Connectors and the Wiring
Remove the electrical power from the ECM.
Illustration 3 g02138858
Location of the ECM connectors (left side engine view)
(1) J1/P1 ECM connectors
(2) J2/P2 ECM connectors
Thoroughly inspect connectors (1) and (2). Inspect all of the connectors that are associated with the sensors. Refer to Troubleshooting, "Electrical Connectors - Inspect" for details.
Illustration 4 g02138860
Terminal locations at the P1 ECM connector for the analog sensor supply and the digital sensor supply
(P1-2) Analog sensor supply
(P1-3) Analog sensor return
(P1-4) Digital sensor supply
(P1-5) Digital sensor return
Illustration 5 g02138917
Terminal locations at the P2 ECM connector for the analog sensor supplies
(P2-30) Analog sensor return
(P2-72) Analog sensor supply
(P2-81) Analog sensor supply
(P2-82) Analog sensor supply
(P2-83) Analog sensor return
(P2-92) Analog sensor return
Perform a 45 N (10 lb) pull test on each of the wires in the ECM connectors that are associated with the circuit.
Check the allen head screw for each of the ECM connectors for the proper torque. Refer to Troubleshooting, "Electrical Connectors - Inspect" for details.
Check the harness and wiring for abrasion and for pinch points from the sensors back to the ECM. Expected Result:All connectors, pins, and sockets are coupled and/or inserted and the harness and wiring are free of corrosion, of abrasion and of pinch points.Results:
OK - The harness and connectors appear to be OK. Proceed to Test Step 2.
Not OK - There is a problem with the connectors and/or wiring.Repair: Repair the connectors or wiring and/or replace the connectors or wiring. Ensure that all of the seals are properly in place and ensure that the connectors are coupled.Verify that the repair eliminates the problem.STOPTest Step 2. Check for Diagnostic Codes that are Active or Logged
Connect Caterpillar Electronic Technician (ET) to the service tool connector.
Restore electrical power to the ECM.
Monitor the active diagnostic code screen on Cat ET. Check and record any diagnostic codes that are active or logged. Look for the following diagnostic codes:
41-3
41-4