RECEPTACLE AS 2908858 - Caterpillar

Illustration 1 g01294996
Connections for the bypass switch on the hydraulic oil filterThis diagnostic code is associated with the bypass switch on the hydraulic oil filter. The "Input low error" means that the module has determined that the voltage of the circuit for the switch is below normal. The filter bypass switch contacts are normally closed to ground below the actuaction pressure. When the hydraulic filter is clogged, the pressure will increase and the contacts will open.The possible causes of this diagnostic code are listed below:
The signal circuit for the switch is shorted to ground.
The switch has failed.
The module has failed. This is unlikely.Note: The following test procedure may create other diagnostic codes. Ignore these created diagnostic codes and clear the diagnostic codes when the original diagnostic code has been corrected. Ensure that the diagnostic code of Input low error for pin 25 of the IQAN-XT2 module is active before performing this procedure.Note: Use a digital multimeter for the measurements in this procedure.Test Step 1. CHECK THE SWITCH
Turn the key start switch and the disconnect switch to the ON position. Do not start the engine.
Disconnect the machine harness connector from the switch. Observe the diagnostic code.Expected Result:The Input low error diagnostic code changed to an Input high error diagnostic code when the switch was disconnected.Results:
YES - The Input low error diagnostic code changed to an Input high error diagnostic code when the switch was disconnected. The switch is causing the problem.Repair: The switch is faulty. Replace the pressure switch.STOP
NO - The status of the Input low error diagnostic code did not change when the switch was disconnected. The switch is not causing the problem. Proceed to Test Step 2.Test Step 2. CHECK THE SUPPLY CIRCUIT FOR A SHORT TO GROUNDThe machine harness connector remains disconnected from the switch.
Turn the key start switch and the disconnect switch to the OFF position.
Disconnect the machine harness connector from the IQAN-XT2 module.
At the machine harness connector for the module, measure the resistance from switch supply contact IQAN XT2 A0 - 25 (wire E455-BR) to frame ground.Expected Result:The resistance measurement is greater than 5000 ohms.Results:
YES - The resistance measurement is greater than 5000 ohms. The circuit is not shorted to ground. Proceed to Test Step 3.
NO - The resistance measurement is less than 5000 ohms. There is a short to in the machine harness.Repair: The switch supply circuit is shorted to a ground source. Refer to the complete machine Electrical System Schematic. Examine all connections in the switch circuit for a short to ground. Check the machine harness for locations where contact with the machine frame can occur. Repair the machine harness or replace the machine harnessSTOPTest Step 3. CHECK THE STATUS OF THE DIAGNOSTIC CODE
Inspect the harness connectors and clean the contacts of the harness connectors and check the wires for damage to the insulation that is caused by excessive heat, battery acid, or chafing.
Perform a 45 N (10 lb) pull test on each of the wires that are associated with the circuit.
Reconnect all