2010 Cadillac Truck SRX AWD V6-2.8L Turbo Page 1855

2010 Cadillac Truck SRX AWD V6-2.8L Turbo Page 1855

4. Operate the vehicle within the Conditions for Running the DTC to verify the DTC does not reset. You may also operate the vehicle within the

conditions that you observed from the Freeze Frame/Failure Records data.

Repair Instructions

Perform the Diagnostic Repair Verification (See: Verification Tests) after completing the diagnostic procedure.

P2227

DTC P2227, P2228, or P2229 (LAU)

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic System

Check - Vehicle) prior to using this diagnostic procedure.

* Review Strategy Based Diagnosis (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Strategy Based Diagnosis) for an

overview of the diagnostic approach.

* Diagnostic Procedure Instructions (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic Procedure

Instructions) provides an overview of each diagnostic category.

DTC Descriptors

DTC P2227

- Barometric Pressure (BARO) Sensor Performance

DTC P2228

- Barometric Pressure (BARO) Sensor Circuit Low Voltage

DTC P2229

- Barometric Pressure (BARO) Sensor Circuit High Voltage

Circuit/System Description

The barometric pressure (BARO) sensor responds to changes in altitude and atmospheric conditions. This gives the engine control module (ECM)

an indication of barometric pressure. The ECM uses this information to calculate fuel delivery. The BARO sensor is located within the controller

and is not serviced as a separate unit. The BARO sensor provides a voltage signal to the ECM relative to the atmospheric pressure changes. The

ECM monitors the BARO sensor signal for a voltage outside of the normal range.

Conditions for Running the DTC

P2227

* Before the ECM can report DTC P2227 failed, DTCs P0100, P0101, P0102, P0103, P0111, P0112, P0113, P0114, P0121, P0122, P0123,

P0221, P0222, P0223, P0236, P0237, P0238, P2228, and P2229 must run and pass.

* The engine is operating.

* The engine speed is less than 1,120 RPM.

* The throttle position sensor parameter is less than 10 %.

* DTC P2227 runs whenever the above conditions are met.

P2228 or P2229

* The ignition is ON.

* The DTCs run continuously when the above condition is met for 0.2 s.

Conditions for Setting the DTC

P2227

* The ECM detects that the BARO sensor signal plus a calibrated threshold is less than the boost pressure sensor signal plus a calibrated

threshold for more than 9 s.

OR

* The ECM detects that the BARO sensor signal plus a calibrated threshold greater than the boost pressure sensor signal plus a calibrated

threshold for more than 9 s.

OR

* The ECM detects that the BARO pressure changed greater than 5 kPa (0.7 psi) within 20 s.

OR

* The ECM detects that the BARO pressure changed greater than 10 kPa (1.5 psi) since the last ignition cycle.

P2228

* The ECM detects that the BARO sensor voltage is less than 0.20 V for 0.5 s.