Navistar International DT 466 Diagnostic/Troubleshooting Manual page 508

504 7 ELECTRONIC CONTROL SYSTEMS DIAGNOSTICS
Figure 486 MAP circuit diagram
WARNING: To avoid serious personal injury, possible death, or damage to the engine or vehicle,
always disconnect main negative battery cable first. Always connect the main negative battery cable
last.
Circuit Checks for MAP Sensor (Use EST, DMM, breakout harness, and 500 Ohm Resistor Harness.)
Test Condition
Sensor disconnected using EST
Voltage from Pin 2 (Blue) to
ground using DMM
500 Ohm Resistor Harness
connected between Pin 3
(Green) and Pin 2 (Blue) of
breakout harness using EST.
Resistance from Pin 1 (Black)
of breakout harness to Pin A of
connector 9260 using DMM
Connect engine harness to sensor. Use the EST to clear DTCs. If an active code remains after
checking test conditions, replace the MAP sensor.
Read all safety instructions in the "Safety Information" section of this manual before doing any procedures.
Spec Checks
0 V If voltage > 0.039 V, check signal circuit for short to V
or B+.
5 V ±0.5 V If voltage > 5.5 V, check V
< 4.5 V, check V
5 V
If voltage < 4.9 V, check signal circuit for open or short
to ground.
— Disconnect connector 9260
from Pin 3 to Pin A of connector 9260 (spec > 1 kΩ)
to check for short to ground within wiring harness.
— Disconnect negative battery cable. Measure
resistance from Pin 3 to ground cable to check for
short to ground.
— Use a breakout box from Pin 3 to Pin X2–8 (spec < 5
Ω) to check for open in the harness.
< 5 Ω If resistance is > 5 Ω, check for open or high resistance
between ECM and sensor connector. Use a breakout
box and measure resistance from between Pin 1 and Pin
X1–6 (spec < 5 Ω).
EGES-270-1
Follow all warnings, cautions, and notes.
© August 2008 Navistar, Inc.
for short to B+. If voltage is
REF
for open or short to ground.
REF
1
. Measure resistance
REF