Table 1. 342 Engine Speed Sensor Diagnostic Codes.
CID FMI CODE
TEST OR INSPECTION
342-8 Engine Speed Sensor
Signal Is an Abnormal
· 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
Engine ECM detects an intermittent loss of signal or a complete loss of signal
from the secondary speed/timing sensor for 2 seconds.
· Engine control wiring harness is open.
· Secondary engine speed (cam position) sensor is faulty.
· 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 342-8 Active -
engine (TM 5-3805-298-10) while
Proceed to Test Step 2.
using MSD to check for active
Diagnostic Code 342-8 Not Active -
Troubleshooting is complete.
Test Step 2. Test for Open Engine
Control Wiring Harness.
1. Turn ignition switch and battery
disconnect switch to OFF position