VALVE GP-RELIEF 2562866 - Caterpillar

Illustration 1 g01317373
This diagnostic code is associated with the "Hoe Auxiliary Continuous" Flow Switch. This switch has two inputs to the ECM: normally open (wire M937-GN) and normally closed (wire M936-BR). During normal operation, one switch input is open and the other input is grounded. If each input is in the same state, the ECM will detect a diagnostic code. This diagnostic code is detected when both switch inputs are open at the same time.The possible causes of this diagnostic code are listed:
Short to the + battery terminal.
The circuit is open.
A failed switch
The ECM may have failed. This is unlikely.Note: The following test procedure may create other diagnostic codes. Ignore these created diagnostic codes and clear these diagnostic codes when the original diagnostic code has been corrected. Ensure that the diagnostic code of CID 2736 FMI 03 is active before performing this procedure.Note: Use the 146-4080 Digital Multimeter for the measurements in this procedure.Note: Before performing this procedure, inspect the harness connectors that are involved in the circuit. Poor connections can often be the cause of a problem in an electrical circuit. Verify that all connections in the circuit are clean, that all connections are secure, and that all connections are in good condition. If a problem with a connection is found, correct the problem and verify that this diagnostic code is active before performing this procedure. Test Step 1. CHECK THE CIRCUIT FOR THE SWITCH.
Turn the