FILTER AS-DIESEL PARTICULATE 2940003 - Caterpillar

Illustration 1 g00737908
Schematic for the display power supply
This diagnostic code is recorded when the main display module reads the voltage of the display power supply circuit and the voltage is below normal. Normal display power supply voltage is 9.0 0.5 DCV. The schematic that is shown above represents a typical installation of the component. Verify the connector contact and wire numbers by using the Electrical System Schematic for the machine that is being serviced.Test Step 1. CHECK THE VOLTAGE AT THE MAIN DISPLAY MODULE.
DO NOT disconnect the harness from the module.
Use the 7X-1710 Multimeter Probe Group. Check the voltage at the connector for the main display module. Measure the voltage from contact 34 to contact 2 (ground). Expected Result:The voltage measures 9.0 0.5 DCV.Results:
OK - The voltage is 9.0 0.5 DCV. The display power supply voltage is correct. Check the main display module for the same diagnostic code. If the service code indicator is still ON, the main display module has failed.Repair: It is unlikely that the main display module has failed. Exit this procedure and perform this procedure again. Also, recheck if the diagnostic code indicator is illuminated for this diagnostic code. If the cause of the diagnostic code is not found, replace the main display module. See Testing and Adjusting, "Module - Replace".STOP
NOT OK - The voltage is NOT 9.0 0.5 DCV. The display power supply voltage is NOT correct. Proceed to test step 2.Test Step 2. DISCONNECT THE MODULES.
Use the 7X-1710 Multimeter Probe Group. Check the voltage at the connector for the main display module. Measure the voltage from contact 34 to contact 2 (ground).
Disconnect a module from the machine harness one at a time.
Continue to measure the voltage at the connector for the main display module. Measure the voltage from contact 34 to contact 2. Expected Result:The voltage that is measured is 9.0 0.5 DCV.Results:
OK - The voltage is 9.0 0.5 DCV. The power supply to the module is correct. The module that was just disconnected has failed.Repair: Replace the module that was disconnected.STOP
NOT OK - The voltage is NOT 9.0 0.5 DCV. The display power supply voltage is not correct. Repeat this test step again. All the modules have been disconnected from the machine harness and the voltage is NOT 9.0 0.5 DCV. Proceed to test step 3.Test Step 3. CHECK FOR A SHORT TO GROUND.
Turn the disconnect switch and the key start switch to the OFF position.
Disconnect the machine harness from the main display module.
At the machine harness connector for the main display module, measure the resistance. Measure the resistance between harness connector contact 34 and harness connector contact 2. Expected Result:The resistance that is measured is greater than 5000 ohms.Results:
OK - The resistance is greater than 5000 ohms. STOP
NOT OK - The resistance is less than 5000 ohms. The harness has failed.Repair: Repair the harness or replace the harness.STOP