Aged or contaminated upstream oxygen sensor on bank 2 (sensor 1) that has lost its switching speed; Exhaust leaks upstream of the sensor, allowing outside air to dilute the sample and slow the signal; Wiring damage or corrosion at the sensor connector or along the harness to the PCM; A failing catalytic converter on bank 2 that is not storing oxygen properly, indirectly affecting the monitor; Engine misfire or vacuum leak on bank 2 that alters exhaust gas composition and slows sensor response; Use of leaded fuel or silicone-based sealants that poison the oxygen sensor element

DTC codes / Chrysler codes / P1196

P1196 · ChryslerO2 Sensor 2/1 (Bank 2 Sensor 1) Slow During Catalyst Monitor

P1196 on Chrysler vehicles means the powertrain control module (PCM) detected that the upstream oxygen sensor on bank 2 (sensor 1) is responding too slowly during the catalyst monitor test. The PCM compares the sensor's switching rate against an expected value, and a slow sensor prevents the catalyst efficiency test from completing or causes it to fail.

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 reduced fuel economy as the PCM may default to a richer mixture
Occasional rough idle or hesitation during acceleration if the slow sensor skews fuel trim
Failure of an emissions inspection due to the catalyst monitor not completing
In rare cases, a faint sulfur or rotten egg smell from the exhaust if the mixture runs rich

Common causes, most likely first

Aged or contaminated upstream oxygen sensor on bank 2 (sensor 1) that has lost its switching speed
Exhaust leaks upstream of the sensor, allowing outside air to dilute the sample and slow the signal
Wiring damage or corrosion at the sensor connector or along the harness to the PCM
A failing catalytic converter on bank 2 that is not storing oxygen properly, indirectly affecting the monitor
Engine misfire or vacuum leak on bank 2 that alters exhaust gas composition and slows sensor response
Use of leaded fuel or silicone-based sealants that poison the oxygen sensor element

How to diagnose and fix it

Use a scan tool to verify P1196 is active and check for pending or stored codes that could affect bank 2 fuel control
Inspect the bank 2 sensor 1 wiring and connector for chafing, corrosion, or loose pins, and repair as needed
Perform a smoke test on the exhaust system upstream of the sensor to rule out leaks
Check live data for the bank 2 sensor 1 switching rate and compare it to the bank 1 sensor 1; a noticeably slower or lazy pattern confirms sensor degradation
Test the sensor's heater circuit resistance and supply voltage to rule out a heater fault that could mimic slow response
Replace the bank 2 sensor 1 oxygen sensor with a quality direct-fit unit, then clear codes and complete a drive cycle to run the catalyst monitor
If the code returns after sensor replacement, inspect the bank 2 catalytic converter for efficiency and check for engine misfire or fuel trim issues

Why a slow O2 sensor fools the catalyst monitor

A lazy upstream oxygen sensor can pass a simple voltage swing test but still fail the catalyst monitor because the PCM measures switching frequency, not just range.
Exhaust leaks between the engine and the sensor are a common cause of slow response that technicians miss when they focus only on the sensor itself.
A misfire on bank 2 can set P1196 without any oxygen sensor fault, because unburned fuel alters the exhaust pulse and slows the sensor's reaction.
Replacing the catalytic converter before verifying the upstream sensor's switching speed is a costly misdiagnosis, since a slow sensor often mimics a bad converter.
After sensor replacement, the catalyst monitor may take several drive cycles to run, so a pending P1196 immediately after repair does not always mean the fix failed.

Can I keep driving with P1196?

The vehicle is generally safe to drive with P1196 because the fault affects emissions monitoring rather than immediate engine operation. Avoid long-term driving with the light on, as a slow sensor can gradually worsen fuel economy and may lead to catalyst damage if ignored.

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.