2010 Cadillac Truck SRX AWD V6-2.8L Turbo Page 1860

2010 Cadillac Truck SRX AWD V6-2.8L Turbo Page 1860

瀚慖f a condition exists, attempt to clean or dry the atmospheric inlet.

2. Start the engine. Observe the DTC information with a scan tool. DTCs P2227, P2228, or P2229 should not set.

瀚慖f DTC P2227, P2228, or P2229 sets, replace the K20 ECM.

Repair Instructions

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

Control Module References (See: Testing and Inspection/Programming and Relearning) for ECM replacement, setup, and programming

P2232

DTC P2232 (Without 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 P2232

- HO2S Signal Circuit Shorted to Heater Circuit Sensor 2

Circuit Description

The engine control module (ECM) supplies a voltage near 450 mV between the heated oxygen sensor (HO2S) signal circuit and the low reference

circuit. The HO2S varies the voltage over a range from about 1,000 mV when the exhaust is rich, down through about 10 mV when the exhaust is

lean. The ECM monitors and stores the HO2S voltage information. The ECM evaluates the HO2S voltage samples in order to determine the amount

of time that the HO2S voltage was out of range. Or, to detect if the HO2S signal voltage switches at the same rate at which the ECM is

commanding the heater ON and OFF.

Conditions for Running the DTC

* The engine is operating.

* The ignition voltage is greater than 10 volts.

* The calculated exhaust gas temperature is between 250-800掳C (482-1,472掳F) for greater than 90 seconds.

* The HO2S heater control is enabled for greater than 10 seconds.

* DTC P2232 runs continuously once the conditions above exist for greater than 10 seconds.

Conditions for Setting the DTC

* The ECM detects that the HO2S 2 signal voltage increases greater than 2 volts within 0.04 second, in 4 out of 6 HO2S heater switch OFF

samples.

* The condition exists for greater than 4 seconds, or for a cumulative of 30 seconds.

Action Taken when the DTC Sets

DTCs P2232 is a Type B DTC.

Conditions for Clearing the MIL/DTC

DTCs P2232 is a Type B DTC.

Diagnostic Aids

* The HO2S voltage should be between 350-550 mV with the ignition ON. If the voltage is greater than the specified value, there is a condition

with the HO2S circuits. If the voltage does not change after disconnecting the HO2S, the condition is between the sensor and the ECM. If the

voltage is between 350-550 mV after disconnecting the sensor, the condition is with the HO2S.

* Inspect the HO2S harness connector for water intrusion. Moisture in a connector may cause voltage to bleed to other circuits within the