Table 1. 0274 Atmospheric Pressure Sensor Diagnostic Codes.
TEST OR INSPECTION
Pressure Sensor Voltage
· Always inspect harness connectors that are involved in the circuit. Poor
connections can often be the cause of a problem in an electrical circuit.
Verify that all connections in the circuit are clean and secure and that all
connections are in good condition. If a problem with the connection is
found, correct the problem and verify that this malfunction or diagnostic
code is active before performing this procedure.
· Perform open or short-circuit test at each harness connection to identify
the correct harness to replace.
· Tag all wiring harnesses to aid in installation.
· Perform this test only if condition is active.
DIAGNOSTIC CODE SET CONDITION
Engine ECM Detects Above Normal Voltage on Atmospheric Pressure Sensor
Signal Circuit R747.
· Basic Engine Wring Harness High Resistance, Open, or Shorted.
· Atmospheric Pressure Sensor.
· Engine ECM.
Test Step 1. Test Sensor 5-Volt and
Ground Circuit Function.
1. Turn ignition switch and battery
disconnect switch to OFF position
2. Remove four bolts
(Figure 1, Item 1), washers
(Figure 1, Item 2), bushings
(Figure 1, Item 3), and splash
shield (Figure 1, Item 4) from
Figure 1. Splash Shield and Retaining Hardware.