RING 5S7878 - Caterpillar

Use this procedure to troubleshoot a problem with a sensor supply. Also, use this procedure if one of the following diagnostic codes is active or easily repeated.
Table 1
J1939 Code and Description CDL Code and Description Comments
100-21
Engine Oil Pressure : Data Drifted Low 100-21
Engine Oil Pressure Sensor : Data Drifted Low The 5 VDC supply to the sensor has been lost.
The code is logged.
101-21
Engine Crankcase Pressure : Data Drifted Low 101-21
Crankcase Air Pressure Sensor : Data Drifted Low The 5 VDC supply to the sensor has been lost.
The code is logged.
108-21
Barometric Pressure : Data Drifted Low 3528-21
Barometric Pressure Sensor : Data Drifted Low The 5 VDC supply to the sensor has been lost.
The code is logged.
109-21
Engine Coolant Pressure : Data Drifted Low 2302-21
Engine Coolant Pump Outlet Pressure Sensor : Data Drifted Low The 5 VDC supply to the sensor has been lost.
The code is logged.
1208-21
Engine Pre-filter Oil Pressure : Data Drifted Low N/A The 5 VDC supply to the sensor has been lost.
The code is logged.
3358-21
Engine Exhaust Gas Recirculation Inlet Pressure : Data Drifted Low 3385-21
EGR Intake Pressure Sensor : Data Drifted Low The 5 VDC supply to the sensor has been lost.
The code is logged.
3563-21
Engine Intake Manifold #1 Absolute Pressure : Data Drifted Low 1785-21
Intake Manifold Pressure Sensor : Data Drifted Low The 5 VDC supply to the sensor has been lost.
The code is logged.
5578-21
Engine Fuel Delivery Absolute Pressure : Data Drifted Low 289-21
Fuel Pressure Sensor - Before Fuel Filter : Data Drifted Low The 5 VDC supply to the sensor has been lost.
The code is logged.
5580-21
Engine Filtered Fuel Delivery Absolute Pressure : Data Drifted Low 460-21
Fuel Pressure Sensor - After Fuel Filter : Data Drifted Low The 5 VDC supply to the sensor has been lost.
The code is logged.
5708-21
Engine Coolant Pressure #2 : Data Drifted Low N/A The 5 VDC supply to the sensor has been lost.
The code is logged. The Electronic Control Module (ECM) supplies a regulated voltage of 5.0 0.2 VDC to the sensors.The 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. 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 diagnostic codes are active, a sensor may have been damaged. Repair the sensor supply and check for any active sensor diagnostic codes to determine if a sensor has been damaged.
Illustration 1 g06081193
Illustration 2 g01240891
Sensor connector
(1) 5 V or 8 V sensor supply
(2) Sensor return
(3) Signal
Table 2
Troubleshooting Test Steps Values Results
1. Check for Codes
A. Connect Cat® Electronic Technician (ET) to the service tool connector.
B. Determine if a code is active or logged.
Codes
Result: A -3 or -4 code is active or logged. Note which ECM is reporting the active code.
Proceed to