Skip the auto shop - Our mechanics make house calls

P2041 OBD-II Trouble Code: Reductant Injector Air Press Sensor Circuit Intermittent

diagnostic check engine light

P2041 code definition

Found in both diesel and gasoline engines, the reductant injector helps reduce the noxious fumes expelled through the particulate filter in a diesel engine and the catalytic converter in gasoline fueled engines. When a malfunction is detected in the reductant injector air pressure sensor circuit by the Powertrain Control Module (PCM), a P2041 trouble code is stored.

Related trouble codes:

What the P2041 code means

A P2041 trouble code means that the PCM has received a variation in the system voltage from the reductant injector air pressure sensor that exceeds manufacturer's limitations. For some vehicle models, multiple drive cycles are needed before the Check Engine light illuminates.

What causes the P2041 code?

Causes of a P2041 trouble code include:

  • Loose, broken, corroded, or other damage to wiring connectors and other components

  • Faulty reductant injector air pressure sensor

  • Severe exhaust leak upstream in the system from the exhaust temperature sensor

  • Decrease in back pressure caused by the installation of an aftermarket off road exhaust system

What are the symptoms of the P2041 code?

The only symptom of a P2041 trouble code is excessive black smoke upon acceleration. Other than this, the only other signs of a P2041 trouble code is the lit Check Engine light and the stored trouble code.

How does a mechanic diagnose the P2041 code?

To successfully diagnose a P2041 trouble code, the mechanic needs an advanced scanner or code reader, a digital volt/ohmmeter, a heat gun, and an infrared thermometer with a laser pointer. In addition to the proper equipment, a mechanic needs to perform the following:

  • Visually inspect all related wiring, connectors, and components for any looseness, fault, or corrosion.
  • After repairing the wiring, connectors, or components, clear the trouble code and test the system.
  • If the code returns, connect the scanner and download any stored trouble codes and flash frame data.
  • The mechanic should also inspect the exhaust gas temperature sensor and the surrounding circuitry.
  • The mechanic should pay particular attention to the wiring and connectors near any hot exhaust components. The mechanic is looking for any heat damage cause by the hot exhaust parts.
  • After replacing any damaged parts, clear the code and retest the system.
  • If the code returns, the mechanic should check the resistance of the exhaust gas temperature sensor using the digital volt/ohmmeter.
  • If the sensor falls within specifications, leave the volt/ohmmeter leads attached and heat the exhaust gas temperature sensor using a heat gun.
  • If everything still checks out, turn the ignition to the ON position and test for reference voltage and a ground signal at the exhaust gas temperature sensor electrical connector.
  • If low voltage is detected, disconnect the PCM and check for continuity on the wire leading to the exhaust gas temperature sensor.
  • Continuity on this circuit might indicate that the PCM is at fault. In this instance, check the PCM for continuity and resistance.
  • Clear the trouble code and clear it before retesting the system to see if the code returns.

Common mistakes when diagnosing the P2041 code

Mechanics most often mistake the oxygen sensor for the exhaust gas temperature sensor. Replacing the oxygen sensor does not fix the problem with the trouble code soon returning.

How serious is the P2041 code?

Other than excessive black smoke from the exhaust pipe, a vehicle owner does not have to worry about any serious issues from the storage of a P2041 trouble code.

What repairs can fix the P2041 code?

Repairing a P2041 trouble code can include:

  • Replacing any faulty or damaged wiring, connectors, or components
  • Exhaust gas temperature sensor replacement
  • Replacing damaged wiring, connectors, or components caused by hot exhaust parts
  • PCM replacement and reprogramming

Additional comments for consideration regarding the P0100 code

If the vehicle owner has installed a high-performance exhaust system on the vehicle, the lack of back pressure, due to no catalytic converter, can cause the storage of a P2041 trouble code. To fix this problem, the mechanic can install an inline resistor, of at least 2.5 ohms, between the signal and ground wires. In addition, the mechanic should leave the exhaust gas temperature sensor disconnected. This causes the PCM to read the sensor resistance and pass it without storing a trouble code. Before removing any emission related components, the mechanic should check any local, state, or federal laws concerning this type of modification.

Need help with a P2041 code?

YourMechanic offers certified mobile mechanics who will come to your home or office to diagnose and repair your vehicle. Get a quote and book an appointment online or speak to a service advisor at 1-800-701-6230.

The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details
Icon-warranty_badge-02

Skip the repair shop, our top-rated mechanics come to you.

At your home or office

Choose from 600+ repair, maintenance & diagnostic services. Our top-rated mechanics bring all parts & tools to your location.

Fair & transparent pricing

See labor & parts costs upfront, so you can book with confidence.

12-month, 12,000-mile warranty

Our services are backed by a 12-month, 12,000-mile warranty for your peace of mind.

Get A Quote

Need Help With Your Car?

Our certified mobile mechanics make house calls in over 2,000 U.S. cities. Fast, free online quotes for your car repair.

GET A QUOTE

More related articles

Veteran and Military Driver Laws and Benefits in Idaho
The state of Idaho offers a number of benefits and perks for those Americans who have either served in an Armed Forces branch in the...
P2428 OBD-II Trouble Code: Exhaust Gas Temperature Too High Bank 1
P2428 code definition A P2428 trouble code signifies that the PCM has detected a problem in the exhaust gas temperature sensor circuit in bank 1, which subsequently contains the number one...
P0291OBD-II Trouble Code: Cylinder 11 Injector Circuit Low
P0291 code definition When your vehicle’s PCM registers the P0291 code, it means that a voltage reading came from the fuel injector circuit – for cylinder number 11’s fuel injector –...


Related questions

Q: Car isn't shifting when pedal is all the way down and is slow.

Your engine management system is going into "limp mode" when the Check Engine light is illuminated, reducing engine power, and quite likely, leaving your automatic transmission in 2nd gear. This is why you are experiencing greatly diminished performance. Turning your...

Q: Looking for info about most common OBD2 Codes

There are two (at least) quite distinct issues in regard to your general request: The first is, once a check engine light illuminates, what are the most "frequent" codes that are stored and thence downloaded, that is what does THAT...

Q: 2009 Nissan Murano has the P0420 trouble code. It says the normal bank 1 issue, but now it says short to VBAT. What is that and how to fix it?

Hi there. From the description you have provided, for your vehicle's P0420 trouble code. I suspect the O2 (Oxygen) sensor you replaced has created an additional concern for your vehicle. Either, the O2 sensor is incorrect by application or is...