TM 10-3930-675-20-1
0021 00-8
ENGINE AMBIENT AIR PRESSURE SENSOR AND CIRCUITS TROUBLESHOOTING - CONTINUED
0021 00
Table 2. Error Code 1222 - Low Voltage Detected at Ambient Air Pressure Sensor Circuit
Troubleshooting Procedures - Continued.
MALFUNCTION
TEST OR INSPECTION
CORRECTIVE ACTION
Error Code 1222 - Low Voltage Detected at
Ambient Air Pressure Sensor Circuit -
Continued
6. Install
breakout
cable
between sensor and sensor
harness connector and place
ignition
switch
in
ON
position.
Measure
signal
voltage from pin C to pin B of
breakout
cable.
Voltage
should be as follows:
If voltage is not as specified,
proceed with the following
steps.
Altitude (Ft.) vs. Voltage
0
=
3.4-4.5V
3K
=
2.8-3.8V
6K
=
2.2-3.2V
9K
=
1.7-2.7V
12K
=
1.2-2.2V
7. Place ignition switch to OFF
position
and
disconnect
ambient air pressure sensor
from
engine
harness.
Disconnect sensor harness
connector from ECU.
8. Measure resistance from pin 6
of sensor harness connector to
chassis ground. Measurement
should be greater than 100k
ohms.
If measurement is not as
specified, notify SRA to replace
engine harness.
