Failed oxygen sensor heater element inside the bank 2 sensor 2 assembly; Damaged or corroded wiring harness between the sensor and the powertrain control module; Blown fuse or faulty relay that supplies power to the oxygen sensor heater circuit; Loose or contaminated electrical connector at the sensor or along the harness; Internal short or open in the powertrain control module heater driver circuit; Exhaust leaks or physical damage to the sensor that compromise its heater circuit

DTC codes / Chrysler codes / P1161

P1161 · ChryslerHO2S Heater Power Stage Circuit Bank 2 Sensor 2

Q: What does code P1161 mean?

HO2S Heater Power Stage Circuit Bank 2 Sensor 2. P1161 on Chrysler vehicles indicates that the powertrain control module has detected an open, short, or excessive current draw in the heater power stage circuit for the downstream oxygen sensor on bank 2. The sensor's heater element is not receiving the commanded voltage or current, which prevents the sensor from reaching operating temperature quickly and can disrupt closed-loop fuel control.

P1161 on Chrysler vehicles indicates that the powertrain control module has detected an open, short, or excessive current draw in the heater power stage circuit for the downstream oxygen sensor on bank 2. The sensor's heater element is not receiving the commanded voltage or current, which prevents the sensor from reaching operating temperature quickly and can disrupt closed-loop fuel control.

SystemPowertrain

Code typeChrysler specific

SeverityMedium

Fix difficultyIntermediate

AreaFuel and air metering

Symptoms you may notice

Illumination of the check engine light, often with no other noticeable symptoms
Slightly rough idle or hesitation during cold starts while the sensor is cold
A decrease in fuel economy as the system stays in open loop longer than normal
Intermittent check engine light that may clear and reset depending on temperature and vibration
Failed emissions test due to an incomplete or failed oxygen sensor monitor
In rare cases, a noticeable sulfur or rotten egg smell from the exhaust if the sensor reads incorrectly

Common causes, most likely first

Failed oxygen sensor heater element inside the bank 2 sensor 2 assembly
Damaged or corroded wiring harness between the sensor and the powertrain control module
Blown fuse or faulty relay that supplies power to the oxygen sensor heater circuit
Loose or contaminated electrical connector at the sensor or along the harness
Internal short or open in the powertrain control module heater driver circuit
Exhaust leaks or physical damage to the sensor that compromise its heater circuit

How to diagnose and fix it

Inspect the oxygen sensor connector and harness for corrosion, chafing, or loose pins, and repair as needed
Check the heater circuit fuse and relay, and replace any failed components
Measure the resistance of the heater element at the sensor connector and compare to the manufacturer's specification
Test for voltage and ground at the sensor connector with the key on to verify the power stage circuit integrity
Backprobe the powertrain control module connector to check for an open or short in the heater driver circuit
Replace the bank 2 sensor 2 oxygen sensor if the heater element is out of specification or the circuit tests good
Clear the diagnostic trouble codes and verify the repair by running the oxygen sensor monitor to completion

Why the heater circuit fails before the sensor

A common oversight is replacing the oxygen sensor without checking the heater circuit fuse and relay, which can leave the new sensor without power and the code returning immediately.
The heater element inside the sensor can fail intermittently when hot, so a resistance test performed on a cold sensor may pass even though the sensor is faulty.
Corrosion inside the connector pins often mimics a failed sensor, and simply cleaning the terminals can resolve the code without any parts replacement.
A shorted heater circuit can draw excessive current and damage the powertrain control module driver, so always check for a short to ground before installing a new sensor.
This code does not always mean the sensor is dead; a poor ground connection at the engine block can cause the heater circuit to test open even when the sensor is good.

Can I keep driving with P1161?

You can usually continue driving with P1161, but avoid extended idling and heavy load until the fault is repaired, because the engine may stay in open loop and run richer than normal. Have the circuit inspected soon to prevent catalytic converter damage and to ensure the vehicle passes emissions testing.

Tools that help

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Guidance is general and written for Chrysler vehicles. Exact tests and values vary by model, so confirm the fault before replacing parts.