Table 1. 91 Throttle Position Sensor Diagnostic Codes.
CID FMI CODE
TEST OR INSPECTION
91-3 Throttle Position
Sensor Signal Voltage Is
· Always inspect wiring harness connectors that are involved in the circuit.
Above Normal or the
Poor connections can often be the cause of a problem in an electrical
Voltage Is Shorted High
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
Engine electronic control module (ECM) detects signal voltage for the throttle
position is above the diagnostic upper limit that is set for the application.
· Engine wiring harness is shorted to voltage.
· Lower cab wiring harness is shorted to voltage.
· Engine ECM.
Test Step 1. Check for Active
1. Connect MSD and select C6.6 924
2. Start engine or attempt to start
Diagnostic Code 91-3 Active -
engine (TM 5-3805-298-10) while
Proceed to step 3.
using MSD to check for active
Diagnostic Code 91-3 Not Active -
Troubleshooting is complete.
Diagnostic Code 41-3 or 41-4 Active
active engine diagnostic code 41.
- Repair diagnostic code 41 first
Diagnostic Code 41-3 or 41-4 Not
Active - Proceed to Test Step 2.