Navistar International DT 466 Diagnostic/Troubleshooting Manual page 458

454 7 ELECTRONIC CONTROL SYSTEMS DIAGNOSTICS
4. If code is active, do step 6 and 7 to check circuit
for the IAT sensor using the following table.
• Circuit Checks for IAT Sensor
5. If code is inactive, wiggle connectors and wires
at all suspected problem locations.
continuity is interrupted, the EST will display
DTCs related to the condition.
6. Disconnect chassis harness from temperature
sensor.
NOTE: Inspect connectors for damaged pins,
corrosion, or loose pins. Repair if necessary.
7. Connect Temperature Sensor Breakout Harness
to engine harness only.
Circuit Checks for IAT Sensor (Use EST, breakout harness, 3-Banana Plug Harness, and 500 Ohm
Resistor Harness.)
Test Condition
Sensor disconnected
3-Banana Plug Harness
connected between Pin 1
(Green) and Pin 2 (Black) of
breakout harness
500 Ohm Resistor Harness
connected between Pin 1
(Green) and Pin 2 (Black) of
breakout harness
Connect engine harness to sensor. Use the EST to clear DTCs. If an active code remains after
checking test conditions, replace the IAT sensor.
Read all safety instructions in the "Safety Information" section of this manual before doing any procedures.
If circuit
Spec Checks
> 4.6 V
If voltage < 4.6 V, check signal circuit for short to ground.
0 V If voltage is > 0.127 V, check ground and signal circuit
for open or high resistance. Use a breakout box and
measure resistance from Pin 2 to Pin X4–24 and from
Pin 1 to X1–7 (spec < 5 Ω).
< 1.0 V If voltage > 1.0 V, check signal circuit for short to V
or another sensor's signal voltage.
EGES-270-1
Follow all warnings, cautions, and notes.
© August 2008 Navistar, Inc.
, B+,
REF