TM 10-3930-675-20-1
0021 00-2
ENGINE AMBIENT AIR PRESSURE SENSOR AND CIRCUITS TROUBLESHOOTING - CONTINUED
0021 00
Table 1. Error Code 1221 - High Voltage Detected at Ambient Air Pressure Sensor Circuit
Troubleshooting Procedures - Continued.
MALFUNCTION
TEST OR INSPECTION
CORRECTIVE ACTION
Error Code 1221 - High Voltage Detected at
Ambient Air Pressure Sensor Circuit -
Continued
4. Install
breakout
cable
between sensor and sensor
harness
connector.
Place
ignition switch to ON and
measure supply voltage from
pin A to pin B of breakout
cable. Voltage should be
4.75-5.25V.
If voltage is not as specified,
proceed with the following
steps.
5. Disconnect sensor harness
connector from ECU and
place ignition switch in ON
position. Measure voltage at
ECU sensor port from pin 17
to pin 31 of ECU sensor port.
Voltage should be 4.75-
5.25V.
a. If engine harness requires
replacement, notify SRA.
b. If voltage is not as specified,
replace engine ECU (WP 0078
00).
4.75-5.25V
A
B
C