2010 Cadillac CTS Sedan AWD V6-3.0L Page 1923

2010 Cadillac CTS Sedan AWD V6-3.0L Page 1923

瀚慖f a DTC is set, refer to DTC P0641, P0651, P0697, or P06A3 (ECM, LF1) (See: P Code Charts/P0641) for further diagnosis.

2. Ignition ON, observe the scan tool BARO parameter. Compare the parameter to the Altitude Versus Barometric Pressure (See: Powertrain

Management/Computers and Control Systems/Specifications) table. The BARO parameter should be within the specified range indicated in

the table.

3. Engine running observe the DTC information with a scan tool. DTCs P2227, P2228, P2229, or P2230 should not set.

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.

Circuit/System Testing

1. Ignition OFF, disconnect the harness connector at the B17 BARO sensor.

2. Ignition OFF and all vehicle systems OFF. It may take up to 2 minutes for all vehicle systems to power down. Test for less than 5 ohm

between the low reference circuit terminal 2 and ground.

瀚慖f greater than the specified range, test the low reference circuit for an open/high resistance. If the circuit tests normal, replace the K20

ECM.

3. Ignition ON, test for 4.8-5.2 V between the 5 V reference circuit terminal 1 and ground.

瀚慖f less than the specified range, test the 5 V reference circuit for a short to ground or an open/high resistance. If the circuit tests normal,

replace the K20 ECM.

瀚慖f greater than the specified range, test the 5 V reference circuit for a short to voltage. If the circuit tests normal, replace the K20 ECM.

4. Verify the scan tool BARO Sensor parameter is less than 1 kPa (0.2 psi).

瀚慖f greater than the specified range, test the signal circuit terminal 3 for a short to voltage. If the circuit tests normal, replace the K20 ECM.

5. Install a 3 A fused jumper wire between the signal circuit terminal 3 and the 5 V reference circuit terminal 1. Verify the scan tool BARO

Sensor parameter is greater than 127 kPa (18.4 psi).

瀚慖f less than the specified range, test the signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace

the K20 ECM.

6. If the circuits test normal, replace the B17 BARO sensor.

Repair Instructions

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

* Barometric Pressure Sensor Replacement (LF1) (See: Powertrain Management/Computers and Control Systems/Barometric Pressure

Sensor/Service and Repair)

* Control Module References (See: Testing and Inspection/Programming and Relearning) for engine control module replacement, setup, and

programming

P2229

DTC P2227-P2229, or P2230 (LF1)

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