Table 1. 549 Throttle Lock Mode Switch Diagnostic Code.
CID FMI CODE
TEST OR INSPECTION
549-2 Throttle Lock Mode
Switch Data Is Erratic,
· Always inspect wiring harness connectors that are involved in the circuit.
Intermittent, or Incorrect
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
Engine ECM detects an erratic signal, an intermittent signal or an incorrect signal
from the throttle lock mode switch.
· Throttle lock enable switch is faulty.
· Engine wiring harness is open.
· Lower cab wiring harness is open.
· Engine wiring harness is shorted.
· Lower cab wiring harness is shorted.
· 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 549-2 Active -
Proceed to Test Step 2.
engine (TM 5-3805-298-10) while
using MSD to check for active
Diagnostic Code 549-2 Not Active -
Troubleshooting is complete.