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All codes › P0136 › 2022 Toyota Camry

P0136 on a 2022 Toyota Camry

Post-Cat O2 Sensor Circuit Fault (Bank 1)

Severity: moderate Safe to drive (short term) Mid-size Sedan 2020-2024 Toyota Camry

What does P0136 mean on a 2022 Toyota Camry?

P0136 is set when the ECM detects a general circuit fault on the Bank 1 downstream (post-catalyst) oxygen sensor. Unlike the more specific P0137 (low voltage), P0138 (high voltage), or P0140 (no activity), P0136 is the generic circuit code that covers wiring issues, intermittent connection problems, or signals that go outside expected ranges in a way that doesn't fit a more specific fault category.

Symptoms on a 2022 Toyota Camry

Likely causes on a 2022 Toyota Camry

  1. Failed Bank 1 downstream O2 sensor Most common
    Estimated repair: $150– $450
  2. Damaged sensor wiring (chafed against exhaust) Common
    Estimated repair: $80– $350
  3. Corroded O2 sensor connector Common
    Estimated repair: $30– $200
  4. Exhaust leak upstream of the downstream sensor Occasional
    Estimated repair: $100– $500
  5. Damaged or compressed sensor pigtail from a previous repair Occasional
    Estimated repair: $80– $300
  6. Failed PCM input (rare) Rare
    Estimated repair: $400– $1,500

How to diagnose this on a 2022 Toyota Camry

  1. Read all O2-related codes to refine the picture

    P0136 alone is generic. With P0137 it points at low voltage specifically; with P0138 at high voltage; with P0140 at no activity at all; with P0141 at the heater. Cross-referencing tells you whether the diagnostic should target wiring, sensor element, or heater.

    Tools: Scan tool with full code retrieval

  2. Inspect the sensor wiring

    Trace the downstream sensor's harness from the sensor body back to the chassis connector. Look for melted insulation (from exhaust contact), chafing against suspension components, or rodent damage. Repair before replacing the sensor.

    Tools: Flashlight, Inspection mirror, Wire repair supplies

  3. Test the sensor connector

    Disconnect and inspect for water intrusion, corrosion, bent pins. Clean with electrical contact cleaner. The downstream connector sits under the vehicle and gets road spray; corrosion is common after a few salt-belt winters.

    Tools: Electrical contact cleaner, Magnifying glass

  4. Graph the sensor signal

    With engine warm and held at 2500 RPM, watch the Bank 1 downstream O2 voltage. A healthy sensor sits relatively steady around 0.6–0.8 V. Rapid switching, signal stuck at one value, or no signal at all confirms a sensor or wiring issue.

    Tools: Scan tool with graphing PIDs

  5. Verify the bias voltage from the PCM

    Disconnect the sensor and key on. The scan tool should still show bias voltage (typically 0.4–0.5 V) at the connector. If not present, the issue is between the connector and the PCM, not the sensor.

    Tools: Scan tool, Multimeter

Known Technical Service Bulletins for the 2020-2024 Toyota Camry

Manufacturers publish Technical Service Bulletins (TSBs) when a known issue affects a specific vehicle. These bulletins come from the NHTSA database for your Toyota Camry.

+14 more TSBs available in MECH AI's TSB explorer for this vehicle.

Common fixes

About the 2020-2024 Toyota Camry

The 2020-2024 Toyota Camry was commonly sold with the following powertrains: 2.5L I4, 3.5L V6, 2.5L Hybrid I4. Common trims include LE, SE, XLE, XSE.

Why P0136 is the catch-all post-cat code

Each O2 sensor has a family of possible codes:

CodeMeaning
P0136Generic circuit issue (catch-all)
P0137Voltage too low (open or short to ground)
P0138Voltage too high (short to power or rich condition)
P0140No activity detected (sensor isn’t reporting anything)
P0141Heater circuit fault

When the ECM detects a problem that doesn’t fit the more specific patterns, it falls back to P0136. Reading other codes alongside narrows the diagnosis significantly — P0136 alone is much harder to pin down than P0136 + P0140.

What “downstream sensor” actually monitors

The Bank 1 downstream sensor is mounted in the exhaust after the catalytic converter on Bank 1 (the cylinder bank containing cylinder #1). Its main job is catalyst monitoring — comparing its signal to the upstream sensor’s signal to determine whether the catalyst is still scrubbing exhaust gases.

It provides a secondary, slower fuel-trim correction layer on top of upstream-sensor closed-loop control, but it is not the primary fuel feedback. A bad downstream sensor primarily affects emissions monitoring rather than drivability.

OEM vs aftermarket sensors

The downstream sensor’s role is comparison, not raw measurement, so it is slightly less picky about sensor response curve than the upstream. But aftermarket sensors still produce inconsistent results; for $30 more, an OEM Bosch, Denso, or NTK sensor is worth it on a vehicle you plan to keep.

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