UNIVERSAL JOINT GP 8V6175 - Caterpillar

Illustration 9 g01150972
Pin locations on ECM connector
(5) AP sensor/switch common
(41) Input 11 "A/C high pressure switch"
Verify that Cat ET is connected to the data link connector.
Turn the ignition key switch to the OFF/RESET position.
Disconnect the ECM vehicle harness connector J1/P1.
Remove J1/P1-41 (Output 11) from the vehicle harness connector P1.
Install a breakout T between connectors J1 and P1.
Fabricate a jumper wire 100 mm (4 inch) long. Crimp a Deutsch pin to both ends of the wire.
Connect the jumper wire to J1/P1-5 (AP sensor/switch common) and to J1/P1-41 (Input 11) of the breakout T. Refer to illustration 9.
Turn the ignition key switch to the ON position.
Access the "A/C High Pressure Switch" status screen on Cat ET.
Remove the jumper wire and then insert the jumper wire. At the same time, watch the "A/C High Pressure Switch" status on Cat ET. Expected Result:The status screen indicates that the "A/C High Pressure Switch" status is OFF when the jumper wire is in place. The status screen indicates ON when the jumper wire is removed.Results:
Yes - The ECM is OK.Repair: If a problem still exists, then the problem is in the OEM wiring harness. Repair the problem or send the vehicle to the OEM dealer for repair. Verify that the repair eliminates the problem.STOP
No - There may be a problem with the ECM.Repair: Temporarily connect a test ECM. Ensure that the "A/C Pressure Switch Fan On-Time" parameter is programmed in the same manner as the suspect ECM. Use Cat ET to check the ECM. If the problem is resolved with the test ECM, install the suspect ECM. If the problem returns with the suspect ECM, replace the ECM.Verify that the repair eliminates the problem.STOPTest Step 8. Use Cat ET to Check Inlet Manifold Air Temperature and the Engine Coolant Temperature
Verify that Cat ET is connected to the data link connector.
Start the engine.
Access the status for the "Coolant Temperature" and the "Inlet Manifold Air Temperature" on Cat ET.
Start the engine. Monitor the status screen for a few minutes in order to verify that the temperatures are changing as the engine warms up. Expected Result:The "Coolant Temperature" and the "Inlet Manifold Air Temperature" appear to have the correct reading.Results:
Yes - The "Coolant Temperature" and the "Inlet Manifold Air Temperature" appear to have the correct reading. Proceed to Test Step 9.
No - The "Coolant Temperature" or the "Inlet Manifold Air Temperature" appear to be incorrect.Repair: Temporarily connect another sensor. Test the new sensor by checking "Inlet Manifold Air Temperature" and "Coolant Temperature" again. If the problem is resolved with the new sensor, then install the old sensor in order to verify that the problem returns. If the problem returns, then replace the old sensor.Verify that the repair eliminates the problem.STOPTest Step 9. Use the "Cooling Fan Solenoid Special Test" on Cat ET to Check the Circuit
Illustration 10 g01150974
Pin locations on breakout T
(13) Output 4
(11) Output 5
(67) - Battery
Verify that Cat ET is connected to the data link connector.
Verify that the ignition key switch is in the ON position.
Access the