804264 Mercury WASHER

Illustration 1 g01371475
Schematic of the sensor circuit for the PWM sensor
Table 1
Troubleshooting Test Step Values Result
1. Verify that the "Exhaust Temperature Sensor Installation Status" is Programmed Correctly
A. Remove eletrical power from the ECM.
B. Connect Caterpillar Electronic Technician (ET) to the service tool connector.
C. Restore electrical power to the ECM.
D. Establish communication with the ECM.
E. Verify that the "Exhaust Temperature Sensor Installation Status" parameter is programmed to "Installed".
F. Remove electrical power from the ECM. The "Exhaust Temperature Sensor Installation Status" parameter is programmed to "Installed". Result: The "Exhaust Temperature Sensor Installation Status" parameter is programmed correctly.
Proceed to Test Step 2.
Result: The "Exhaust Temperature Sensor Installation Status" parameter is not programmed correctly.
Program the "Exhaust Temperature Sensor Installation Status" parameter.
Illustration 2 g01176458
Location of the ECM connectors that are for the exhaust temperature sensor (left side engine view)
(1) J2/P2 ECM connectors
Illustration 3 g01371895
Location of the sensor connector that is for the exhaust temperature sensor (rear engine view)
(2) Connector for the exhaust temperature sensor
Illustration 4 g01371905
Terminal locations at the P2 ECM connector that are for the exhaust temperature sensor
(P2-29) Digital sensor supply
(P2-39) Exhaust temperature
(P2-92) Digital return
Illustration 5 g01159881
Terminal locations at the connectors for the exhaust temperature sensor
(Terminal A) Digital sensor supply
(Terminal B) Digital return
(Terminal C) Exhaust temperature
Table 2
Troublshooting Test Steps Values Result
2. Inspect the Electrical Connectors and the Wiring
A. Thoroughly inspect connectors (1) and (2). Refer to Troubleshooting, "Electrical Connectors - Inspect" for details that are related to inspection of the electrical connectors.
B. Perform a 45 N (10 lb) pull test on each of the wires in the ECM connector and the engine interface connector that are associated with the circuit.
C. Check the allen head screw on each ECM connector for the proper torque. refer to Troubleshooting, "Electrical Connectors - Inspect" for the correct torque values.
D. Check the harness and the wiring for abrasion and for pinch points.
All connectors, pins, and sockets are completely coupled and/or inserted, and the harness and wiring are free of corrosion, of abrasion and of pinch points.
Result:
The connectors and wiring appear to be OK.
Proceed to Test Step 3.
Result:
The connectors and/or wiring are not OK.
Repair the connectors or wiring and/or replace the connectors or wiring.
3. Check the Supply Voltage at the Sensor
A. Disconnect the exhaust temperature sensor at the harness connector.
B. Restore electrical power to the ECM. Turn the keyswitch to the ON position.
C. Measure the voltage across terminal A (digital sensor supply) and terminal B (digital return) on the harness side of the connector.
D. Remove electrical power from the ECM. Turn the keyswitch to the OFF position.
E. Restore the wiring to the original configuration.
The supply voltage measures 24 2 VDC at the sensor connector.
Result:
The correct supply voltage is measured at the sensor connector.
The sensor is receiving the correct supply voltage. Proceed to Test Step 4
Result:
The voltage is not correct at the sensor connector.
There is a problem in the circuit for the digital sensor supply that is between the ECM and the exhaust temperature sensor. Repair the circuit. Refer to Troubleshooting, "Sensor Supply - Test" for details that are related to troubleshooting a problem with the circuit.
4. Check the Signal Frequency and the Duty Cycle at the Sensor
A. Disconnect the sensor connector from the exhaust temperature sensor.
B. Remove the signal wire from terminal C of the harness side of the connector for the exhaust temperature sensor.
C. Install a 7X-6370 Adapter Cable As (3-PIN BREAKOUT) at the sensor connector.
D. Connect the sensor to the breakout harness.
E. Restore electrical power to the ECM. Turn the keyswitch to the ON position.
F. Measure the frequency and the duty cycle between terminal B (digital return) and terminal C (exhaust temperature) at the 7X-6370 Adapter Cable As (3-PIN BREAKOUT)
G. Remove electrical power from the ECM. Turn the keyswitch to the OFF position.
H.Remove the breakout harness. Restore the wiring to the original configuration.
The frequency is between 400 and 600 Hz. The duty cycle is between 22 and 88 percent.(1)
Result:
The correct supply voltage is measured at the sensor connector.
The sensor is receiving the correct supply voltage. Proceed to Test Step 5.
Result:
The voltage is not correct at the sensor connector.
There is a problem in the circui