Table 1. 172 Intake Manifold Air Temperature Sensor Diagnostic Codes - Continued.
CID FMI CODE
TEST OR INSPECTION
Temperature Sensor Signal
· Always inspect wiring harness connectors that are involved in the circuit.
Voltage Is Below Normal or
Poor connections can often be the cause of a problem in an electrical
the Voltage Is Shorted Low
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 signal voltage from the engine coolant temperature sensor
is less than 0.2 Volts DC for more than eight seconds.
· Engine control wiring harness is shorted to ground.
· Intake manifold air temperature sensor is shorted.
· Engine ECM.
Test Step 1. Check for Active
1. Connect MSD and select C6.6 924
2. Start engine (TM 5-3805-298-10).
Diagnostic Code 172-4 Active -
Using MSD, check for active
Proceed to Test Step 2.
Diagnostic Code 172-4 Not Active -
Troubleshooting is complete.
Test Step 2. Test for Shorted Intake
Manifold Air Temperature Sensor.
1. Turn ignition switch and battery
disconnect switch to OFF position
2. Disconnect connector E-C7
manifold air temperature sensor.