What Is P0135 Code On Chevy Silverado: How To Fix?

Chevy Silverado uses several DTC (Diagnostic Trouble Codes) to notify users about the engine’s irregularities. The P0135 is one of the trouble codes & it’s generated via the PCM. 

If you’re getting this DTC & don’t know what it means, this article is for you. In this article, I’ve discussed everything from symptoms to well-known troubleshooting methods for your help. 

What Does P0135 Code Means On Chevy Silverado? 

P0135 is one of the trouble codes of the Chevy Silverado. By definition, this error code refers to Oxygen Sensor Heater Circuit Malfunction (Bank 1, Sensor 1). Bank 1 means the driver side where sensor one is located. 

The two oxygen sensors help optimize the fuel mixture for the best engine performance. How? They send feedback (of the fuel mixture) to the PCM & let it change the mixture accordingly for better performance.

A certain amount of heat is needed for the oxygen sensor to work. For this reason, both oxygen sensors have built-in heaters & they start working after every start-up. 

The PCM (Powertrain Control Module) monitors how long it takes for the heaters to warm or activate the sensors. If the PCM detects a lesser or longer duration than expected, it generates the DTC P0135. 

Symptoms Of Getting The P0135 Code On Chevy Silverado

Like most other DTCs, the P0135 code also gives plenty of evidence of its existence. Expect to have the code if you’re noticing the following symptoms:

  1. Check Engine Light is On
  2. Rough Driving Experience
  3. Poor Fuel Economy or Low MPG
  4. Excessive Black Smoke From Exhaust
  5. Exhaust Smells Very Bad

In summary, your engine won’t function like it used to do. You’ll be very disappointed with its every move from fuel consumption to the driving experience. 

The Causing Factors Of The Error Code P0135 

This error code doesn’t appear out of the blue. Here are the most common causing factors of the error code P0135:

  1. Blown Circuit or Heater Fuse/s
  2. Damaged Wirings & Connectors 
  3. Faulty HO2S or, Heated Oxygen Sensor
  4. Faulty Powertrain Control Module (Rere Scenario)

Any of these four factors can generate that error code. You can consider yourself lucky if the 4th one isn’t the causing factor of your DTC P1035. 

How Seriousness Is Code P0135 On Chevy Silverado?

This code won’t break your engine, but that doesn’t mean you should ignore it. Any code that is causing the engine light to turn on must be fixed on time. 

This error code means your engine won’t get a proper direction of fuel-oxygen mixing ratio. The wrong ratio will lead to a bumpy driving experience with great fuel wastage. 

How to Solve P0135 Error Code On Chevy Silverado?

You can solve the P0135 error code without rushing to any auto shop (most of the time). However, you’ll need the following equipment to get started:

  • Multimeter 
  • OBD-II Scanner 
  • Repair Manual 

The user manual will help you locate the fuse & oxygen sensors of your specific model.

Assuming you’re ready with the equipment, let’s get started with the troubleshooting methods. 

Check Heater Fuse/s

First of all, you’ve to check the heater fuse – whether it’s blown or not. It’s common for the fuse to blow so that it can protect the sensor. 

Consider replacing the fuse/s if you get any burning smell. Later on, reset the code & see if it appears again after engine start-up. 

Check Wirings & Connectors

After checking the fuse/s, it’s time to check wirings & connectors related to the oxygen sensors. This time, you’ll need a scanner to determine which sensor is faulty & inspect those wirings/connectors visually. 

If you find any inconvenience while inspecting, consider replacing them as soon as possible. You may see a bunch of faulty wirings, take your time & replace them. Don’t forget to clear & re-check the DTC after each operation/replacement. 

Check O2 Sensor With Multimeter

After checking all the possible causes (except PCM), it’s time to check the Oxygen sensor itself. All you’ll need is the multimeter to know whether your O2 sensor is good or bad.

Here are the steps by steps guide on checking O2 sensor with a multimeter:

  • Step 1: Determine the terminals by their name (Terminal 1, 2 & 3)
  • Step 2: Check the repair manual & see the expected voltages from various combinations of two terminals (per test). 
  • Step 3: Conduct necessary tests & see if the values match with the repair manual. 

Chances are – they won’t match & you’ll figure out your O2 sensor is faulty. If so, consider replacing the affected oxygen sensor.

How Much Does It Cost To Solve The Error Code P0135? 

The total cost depends on the replacement parts you’ll be purchasing. For your better understanding, here are the expected prices of the replacements:

  • Fuse Costs $5
  • Oxygen Sensor Costs $200 to $300
  • Wirings & Connectors Can Costs From $100 to $1000

Cherry on top, add the $75 to $150 per hour labor charge if you’re getting the work done from any auto shop. 

Common Mistakes While Solving The P0135 Code

You’re likely to make mistakes if you aren’t cautious enough while fixing this error code. Try to avoid these common mistakes while solving the error code P0135:

  • Not Reading Following The Repair Manual
  • Not Able To Determine The Sensor’s Terminal Numbers Correctly

Additional Comments To Consider Regarding The P0135 Code 

The P0135 isn’t a severe code that you should be panicked about. However, it turns your engine light & that’s the most concerning factor. 

If you let the CEL stay on thinking it’s just the P0135, you’ll be making a huge mistake. Severe codes can also occur & you’ll never know until something terrible happens. 


I hope this article was informative enough to know the error code P0135 thoroughly. Now you can decide whether you can fix it or leave it to an expert technician. 

I recommend solving this code on your own. At least try & see if you succeed doing so. Even if you fail, expert technicians are always there for your help.

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