P0151 Bank 2 sensor 1 oxygen sensor signal is lower than the sensor can normally produce

Bank 2 sensor 1 oxygen sensor circuit low voltage

Monitor

TroubleCodes.net says this code typically causes no symptoms beyond the check engine light because the sensor monitors emissions, so it is usually safe to drive while you book a check.

Source: how we rate severity

P0151 in short

P0151 means the engine computer saw a signal voltage from the bank 2, sensor 1 oxygen sensor that is lower than the sensor can physically produce. A worn sensor, damaged wiring, water in the connector or an exhaust leak near it are the usual causes. Usually only the check engine light comes on.

The upstream oxygen sensor on bank 2 helps the computer fine-tune the fuel mixture. The code sets when its signal voltage drops below the lowest value the sensor should ever give.

TroubleCodes.net points to the sensor itself, which wears with heat, then to wiring damage, corrosion or water, and exhaust leaks near the sensor.

Most likely causes

These are general causes for this code across vehicles. None is specific to one make or model.

  1. Worn or faulty oxygen sensor (bank 2, sensor 1)

    Common general cause
    Why it ranks here
    TroubleCodes.net lists the sensor first and notes a typical life under five years because of heat.
    What would change this
    Rises if wiring tests good and live data stays stuck low. Falls if a wiring fault is found.
    How to test the oxygen (o2) sensor

  2. Wiring, connector or water damage

    Common general cause
    Why it ranks here
    TroubleCodes.net lists damage, corrosion, water entry and connector problems.
    What would change this
    Rises if the harness shows damage or continuity is poor. Falls if continuity is under 1 ohm and there is no short to ground.

  3. Exhaust leak near the sensor

    Possible — needs testing
    Why it ranks here
    TroubleCodes.net says to check for exhaust leaks between the catalytic converter and the sensor.
    What would change this
    Rises if a leak is heard or seen near the sensor. Falls if the exhaust is tight.

What to test first

Start at step 1. Each result tells you what it means and where to go next.

  1. Inspect fuses, harness, connector and sensor for damage, and check for exhaust leaks near the sensor.

    Best left to a shopTool: visual inspection

    Warning:The exhaust is hot enough to burn skin; let it cool fully before touching the sensor or pipe.

  2. Test circuit continuity and compare live sensor data with the other bank.

    Best left to a shopTool: multimeter, scan tool

    Warning:Unplug the sensor with the ignition off, and keep meter leads away from the heater circuit so you do not short it.

Symptoms

  • Check engine light on, often with no other change in how the car drives

How to fix

  1. With the engine off and cool, look over the sensor wire and connector for chafing, burns or water.

Parts and cost context

  • Oxygen (O2) sensor:Confirm the circuit tests good before replacing a sensor. Labour varies; get a quote.

Labor varies by vehicle and shop; get a quote before you approve a repair.

Compare used part prices on PartPriceGuide

On your vehicle

Chrysler

  • 2006 · PT Cruiser

    Supported by vehicle data

    NHTSA flat-file summary of Chrysler bulletin 1801306 (summary: P2152, P0152, P0154, P0151, P0089, P0091 and P0092 are being reported incorrectly in place of P2149, P0132, P0131, P0087 and P0088 on a 2006 PT Cruiser). Whether it is still current is not verified.

  • 2005–2006 · 300

    Supported by vehicle data

    NHTSA flat-file summary of Chrysler bulletin 0803405-chrysler (summary: a lit MIL with a group of codes that includes P0151 (also P0037, P0058, P0131, P0132, P0133, P0138, P0153, P0159)). Whether it is still current is not verified.

  • 1801306Status unverified

    P2152, P0152, P0154, P0151 reported in error

    2006pt-cruiser · issued · NHTSA 10019942

    NHTSA flat-file summary only; the full bulletin was not read. The summary mentions P2152, P0152, P0154, P0151, P0089, P0091 and P0092 are being reported incorrectly in place of P2149, P0132, P0131, P0087 and P0088 on a 2006 PT Cruiser.

    We couldn't confirm whether this bulletin is still current, so it doesn't count as confirmation.

  • 0803405-chryslerStatus unverified

    MIL with oxygen sensor and related codes including P0151

    2005–2006300 · issued · NHTSA 10016925

    NHTSA flat-file summary only; the full bulletin was not read. The summary mentions a lit MIL with a group of codes that includes P0151 (also P0037, P0058, P0131, P0132, P0133, P0138, P0153, P0159).

    We couldn't confirm whether this bulletin is still current, so it doesn't count as confirmation.

Dodge

  • 2006 · Charger

    Supported by vehicle data

    NHTSA flat-file summary of Dodge bulletin 0803405-dodge (summary: a lit MIL with a group of codes that includes P0151 (also P0037, P0058, P0131, P0132, P0133, P0138, P0153, P0159)). Whether it is still current is not verified.

  • 2005–2006 · Magnum

    Supported by vehicle data

    NHTSA flat-file summary of Dodge bulletin 0803405-dodge (summary: a lit MIL with a group of codes that includes P0151 (also P0037, P0058, P0131, P0132, P0133, P0138, P0153, P0159)). Whether it is still current is not verified.

  • 0803405-dodgeStatus unverified

    MIL with oxygen sensor and related codes including P0151

    2005–2006charger, magnum · issued · NHTSA 10016925

    NHTSA flat-file summary only; the full bulletin was not read. The summary mentions a lit MIL with a group of codes that includes P0151 (also P0037, P0058, P0131, P0132, P0133, P0138, P0153, P0159).

    We couldn't confirm whether this bulletin is still current, so it doesn't count as confirmation.

Cadillac

  • 2004 · SRX

    Supported by vehicle data

    NHTSA flat-file summary of Cadillac bulletin 01366 (summary: a lit service engine soon light with oxygen sensor codes P0138 and P0151; the text later adds P0030, P0036, P0050 and P0056). Whether it is still current is not verified.

  • 01366Status unverified

    Service engine soon light with P0138 and P0151

    2004srx · issued · NHTSA 10004150

    NHTSA flat-file summary only; the full bulletin was not read. The summary mentions a lit service engine soon light with oxygen sensor codes P0138 and P0151; the text later adds P0030, P0036, P0050 and P0056.

    We couldn't confirm whether this bulletin is still current, so it doesn't count as confirmation.

  • P0150Oxygen sensor circuit fault on the bank 2 upstream sensor

    Shares causes Possible — needs testing

    Both are bank 2 sensor 1 oxygen sensor circuit codes; read both together and check the shared wiring.

All Oxygen sensors codes

P0151 questions

Is it safe to drive with P0151?

Usually yes, since TroubleCodes.net says the light is typically the only symptom, but fix it so emissions and mixture control stay correct.

Sources and review

  1. P0151 trouble code — TroubleCodes.net
  2. 1801306: P2152, P0152, P0154, P0151 reported in error — Chrysler
  3. 0803405: MIL with oxygen sensor and related codes including P0151 — Chrysler
  4. 0803405: MIL with oxygen sensor and related codes including P0151 — Dodge
  5. 01366: Service engine soon light with P0138 and P0151 — Cadillac
  6. On-Board Diagnostic Trouble Codes (generic code title list) — Delaware Division of Motor Vehicles
Last reviewed
Written by
Saurabh K.
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