GEAR 1T1418 - Caterpillar

Illustration 1 g03506662
Schematic for the pressure sensors on the P1 connector
Not all connectors are shown. Refer to the Electrical Schematic for the application.
Illustration 2 g03374199
Schematic for the pressure sensors on the P2 connector
Illustration 3 g03506663
Pin locations on the P1 connector for the pressure sensors
(33) Fuel pressure sensor ground
(42) Fuel pressure sensor 5 VDC supply
(54) Inlet fuel pressure sensor signal
(55) Outlet fuel pressure sensor signal
(56) Primary fuel pressure sensor signal
Illustration 4 g03374218
Pin locations on the P2 connector for the pressure sensors
(38) Intake manifold pressure sensor ground
(39) Oil pressure sensor ground
(40) Fuel rail pressure sensor ground
(46) Intake manifold pressure sensor 5 VDC supply
(47) Oil pressure sensor 5 VDC supply
(48) Fuel rail pressure sensor 5 VDC supply
(49) Fuel rail pressure sensor signal
(55) Intake manifold pressure sensor signal
(56) Oil pressure sensor signal
Illustration 5 g03374231
Fuel rail pressure sensor
(1) Ground
(2) Signal
(3) 5 VDC Supply
Illustration 6 g01170310
Typical example of an engine pressure sensor
(1) 5 VDC Supply
(2) Ground
(3) Signal
Table 2
Troubleshooting Test Steps Values Results
1. Check for Diagnostic Codes
A. Establish communication between the electronic service tool and the ECM . Refer to Troubleshooting, "Electronic Service Tools", if necessary.
B. Turn the keyswitch to the ON position.
C. Look for a -3, or -4 active or logged codes:
Diagnostic code
Result: A -3 diagnostic code is active.
Proceed to Test Step 2.
Result: A -4 diagnostic code is active.
Proceed to Test Step 3.
2. Create a Short at the Sensor Connector
A. Use a jumper wire in order to create a short between the signal terminal and the ground terminal at the sensor connector.
B. Turn the keyswitch to the ON position.
C. Monitor the diagnostic codes on the electronic service tool. Check for an active -4 diagnostic code for the suspect sensor.
D. Turn the keyswitch to the OFF position.
Short created
Result: A -4 diagnostic code became active after creating the short at the sensor connector.
The wiring is OK. Replace the sensor.
Verify that