Table 1. 793 Primary Steering Oil Pressure Switch Diagnostic Codes.
CID FMI CODE
TEST OR INSPECTION
793-3 Primary Steering
Pressure Switch Voltage Is
· Always inspect wiring 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 and secure and
that all connections are in good condition. If a problem with the
connection is found, correct the problem and verify that this malfunction
or diagnostic code is active before performing this procedure.
· Perform open or short-circuit test at each wiring harness connection to
identify the correct wiring harness to replace.
· Tag all wiring harnesses to aid in installation.
· Perform this test only if condition is active.
DIAGNOSTIC CODE SET CONDITION
Transmission ECM detects status of both primary steering pressure switch
normally open and normally closed inputs are open.
· Primary steering pressure switch is faulty.
· Transmission wiring harness is open.
· Lower cab wiring harness is open.
· Cab ground is open.
· Transmission ECM.
Test Step 1. Check for Active
Connect MSD. Select Transmission
Diagnostic Code 793-3 Active -
924H and check for active diagnostic
Proceed to Test Step 2.
Diagnostic Code 793-3 Not Active -
Troubleshooting is complete.
Test Step 2. Test for Faulty Primary
Steering Pressure Switch.
1. Turn ignition switch and battery
disconnect switch to OFF position
2. Remove right lower cab access
panels (WP 0347).