TM 5-3805-291-23-1
ELECTRICAL SYSTEM TESTS, INSPECTIONS, AND ADJUSTMENTS - CONTINUED
0013 00
ENGINE PRESSURE SENSOR OPEN OR SHORT CIRCUIT TEST
0013 00
N OT E
Use this procedure to troubleshoot anysuspect problems with following sensors:
a.
Fuel pressure sensor.
b.
Engine oil pressure sensor.
c.
Atmospheric pressure sensor.
d.
Right turbo inlet pressure sensor.
e.
Intake manifold pressure sensor.
Use this procedure to troubleshootsystem when one of following diagnostic codes is active or eas-
ily repeated:
a.
94-03 Fuel Pressure Open/Short to +Batt
b.
94-04 Fuel Pressure Short to Ground
c.
100-03 Engine Oil Pressure Open/Short to +Batt
d.
100-04 Engine Oil Pressure Short to Ground
e.
274-03 Atmospheric Pressure Open/Short to +Batt
f.
274-04 Atmospheric Pressure Short to Ground
g.
275-03 Right Turbo Inlet Pressure Open/Short to +Batt
h.
275-04 Right Turbo Inlet Pressure Short to Ground
i.
1785-03 Intake Manifold Pressure Sensor Voltage High
j.
1785-04 Intake Manifold Pressure Sensor Voltage Low
5V sensor supply provides power to all 5V sens rs. ECM supplies 5.0 0.2 VDC to terminal A of
o
each sensor connector.
Sensor return from ECM connector goes to terminal B of each sensor connector.
Sensor supply is output short crcuit protected. A short circuit to battery will not damage circuit
i
inside ECM.
ECM continuously outputs a pull-up volta e on circuit for sensor signal wire.
g
ECM uses this pull-up voltage to detect problem in signal circuit.
When ECM detects presence of voltage that is ab ve a threshold on signal circuit, ECM will gen-
o
erate an 03 diagnostic code for sensor.
If sensor is disconnected at sensor connector, pr sence of pull-up voltage at sensor connector indi-
e
cates that wires from sensor connector to ECM are OK.
If sensor is disconnected at sensor connector, abence of pull-up voltage at sensor connector indi-
s
cates problem in signal wire.
If sensor is disconnected at sensor connectorand voltage at sensor connector is different from
pull-up voltage, signal wire may be shorted to another wire in harness.
