• | Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. |
• | Review Strategy Based Diagnosis for an overview of the diagnostic approach. |
• | Diagnostic Procedure Instructions provides an overview of each diagnostic category. |
Circuit | Short to Ground | High Resistance | Open | Short to Voltage | Signal Performance |
---|---|---|---|---|---|
HO2S Heater Voltage Supply | Opens fuse | P0030, P0036, P0053, P0054, P0135, P0141 | P0030, P0036, P0135, P0141 | -- | P0135, P0141 |
HO2S Heater Low Control | P0030, P0036 | P0030, P0036, P0053, P0054, P0135, P0141 | P0030, P0036, P0135, P0141 | P0030, P0036, P0135, P0141 | P0135, P0141 |
Circuit | Normal Range | Short to Ground | Open | Short to Voltage |
---|---|---|---|---|
HO2S Heater Low Control | 0.5-2 A | 0 A | 0 A | 0 A |
HO2S Heater Voltage Supply | 0.5-2 A | 0 A | 0 A | 1-2 A |
Heated oxygen sensors (HO2S) are used for fuel control and post catalyst monitoring. Each HO2S compares the oxygen content of the surrounding air with the oxygen content in the exhaust stream. The HO2S must reach operating temperature to provide an accurate voltage signal. A heating element inside the HO2S minimizes the time required for the sensor to reach operating temperature. Voltage is provided to the heater by an ignition voltage circuit through a fuse. With the engine running, ground is provided to the heater by the HO2S heater low control circuit, through a low side driver within the powertrain control module (PCM). The PCM uses pulse width modulation (PWM) to control the HO2S heater operation to maintain a specific HO2S operating temperature range.
The PCM determines the temperature by measuring the current flow through the heater and calculating the resistance. Based on the resistance, the PCM can predict the sensor temperature. The HO2S uses PWM to control the heater operation. The PCM calculates the heater resistance on a cold start. This diagnostic will only run once per ignition cycle. If the PCM detects that the heater calculated resistance is not within the expected range, DTC P0053 sets for HO2S 1, or DTC P0054 sets for HO2S 2.
• | DTCs P0112, P0113, P0117, P0118, are not set. |
• | The engine is started. |
• | The ignition is OFF for more than 10 hours. |
• | The Engine Coolant Temperature (ECT) Sensor parameter is between 0-40°C (32-104°F) at engine start-up. |
• | The ECT Sensor parameter minus the Intake Air Temperature (IAT) Sensor parameter is less than 8°C (14°F) at engine start-up. |
• | DTCs P0053 and P0054 run once per drive cycle when the above conditions are met. |
• | The PCM detects that the affected HO2S heater low control circuit is not within a specified range at engine start-up. |
• | DTCs P0053 and P0054 set within 1 second when the above condition is met. |
DTC P0053 and P0054 are Type B DTCs.
DTC P0053 and P0054 are Type B DTCs.
Powertrain Diagnostic Trouble Code (DTC) Type Definitions
Important: You must perform the Circuit/System Verification before proceeding with Circuit/System Testing.
⇒ | If the test lamp does not illuminate, test the HO2S heater voltage supply circuit for a short to ground or an open/high resistance. If the circuit tests normal and the HO2S heater voltage supply circuit fuse is open, test all components connected to the fuse and replace as necessary. |
⇒ | If the lamp illuminates, test the HO2S heater low control circuit for a short to ground. If the circuit tests normal, replace the PCM. |
⇒ | If the test lamp is not on steady or flashing, test the HO2S heater low control circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the PCM. |
Important:
• The output driver should detect a short to voltage and turn OFF. If a resistance fault is present the driver will remain ON and the scan tool will display more than 0.0A. Less than 10 ohms of resistance may set a DTC. • Performing this test may set additional DTCs.
⇒ | If more than the specified range, test the HO2S heater voltage supply and HO2S heater low control circuits for more than 1 ohm of resistance. If the circuits test normal, replace the PCM. |
Notice: Refer to Heated Oxygen Sensor Resistance Learn Reset Notice in the Preface section.
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
• | Control Module References for replacement, setup, and programming |