How to Troubleshoot & Fix P0038 Jeep DTC Code? (In-Depth Guide)

The P0038 is a diagnostic trouble code (DTC) triggered by the powertrain control module. It indicates a high heater control circuit and is considered moderately severe to severe.

The code is stored for various reasons, and you must find the exact reason for the code to appear. In this blog, we will discuss troubleshooting steps and fixes to solve the code P0038 on the Jeep. 

What Does P0038 Jeep Code Mean?

The error code P0038 on Jeep vehicles means “H02S Heater Control Circuit High (Bank 1 Sensor 2).” It may be triggered when your vehicle’s control module detects a fault in the heater circuit and oxygen sensor bank 1 sensor 2. 

The oxygen sensor on a car determines the volume of exhaust gases and sends the data to the PCM. The PCM uses it in fuel metering for better emission control.

Nowadays, the oxygen sensor, or heated oxygen sensor, consists of heating elements. Because the oxygen sensor is designed to be at a particular operating temperature to monitor the quantity of oxygen more accurately. 

The heating element heats the oxygen sensor before the engine warms up, which reduces the time to count the oxygen volume. However, the PCM always monitors the voltage inside the heater circuit of the sensor. 

When it detects a higher voltage in the heater circuit than normal, it sets the code P0038 on the dashboard. 

Here’s a breakdown of the code P0038 on Jeep vehicles:

  • P = It stands for “powertrain” which includes the engine, transmission, and other drivetrain components. 
  • 0 = It means the code is generic.
  • 0 = Fuel and air metering or emission control issues.
  • 38 = specific fault index (here, H02S heater control circuit high).

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P0038 Code: What Causes the Oxygen Sensor to Gain High Voltage on the Jeep?

There are multiple issues that can cause the heated oxygen sensor on the bank one to gain high voltage. These causes include:

  • Bad Heated Oxygen Sensor (HO2S) Bank 1
  • The O2 sensor circuit fuse is blown.
  • Faulty electrical connections or wiring harness 
  • Bad heater elements
  • Faulty engine control module (ECM)

How to Troubleshoot & Fix P0038 Jeep Code?

Now that we know the possible causes of the code P0038 on Jeep, here are the possible troubleshooting steps you can follow to detect the main culprit. You will also have a quick idea about the potential solutions to each problem. 

1. Check the Electrical Connection and Wiring Harness on Bank 1 Sensor 2:

Start by checking the electrical connections and wiring harness on bank 1, and oxygen sensor 2. Also, check the metal tabs for any damages. 

If any damage is found, repair or replace the wire harness as required. The repair cost of a bad electrical connection or wire harness will be around $55 to $105. Here, the labor cost is between $35 and $45, while the parts may cost between $20 and $60.

But if any damage is not found, attempt the next troubleshooting step.

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2. Examine the Heated O2 Sensor Fuse:

Once you have checked the electrical connections on bank 1 sensor 2 and found them working well, then determine the fuse for the heated oxygen 2 sensors. There are two fuses for the heater circuit of the oxygen O2 sensor. 

One is downstream and another is upstream, and both of these fuses are 15 amps. The fuses are located in the fuse box in the engine compartment. 

Once you have located the fuses, check their resistance using a multimeter. If there is no beep in the multimeter or it shows the reading ‘OL’, then the fuse must be blown and needs to be replaced. 

It will typically cost between $75 and $105 to replace a blown heated oxygen sensor 2 bank 1 fuse on a Jeep. The labor cost can be charged between $65 and $75 per hour, while a new fuse will cost around $10 to $20. 

3. Inspect the Heater Elements:

If you find there is no damage to the fuse, then check the resistance at the heater element. Test the ground for the oxygen sensor 2 bank 1 with a multimeter. 

After checking, if you get unlimited resistance at the ground, the ground wire needs to be replaced. 

Typically, the cost of replacing a bad ground wire on oxygen sensor 2 bank 1 is $100 to $180. Here, you may need to pay $80-$100 for the labor cost and $20-$100 for the new parts.

Read Also: How to Troubleshoot & Fix P0128 Jeep Grand Cherokee Code?

4. Check the Heated Oxygen Sensor on Bank One:

If you find there is no problem with the earring connectors and the resistance of the heater, you can suspect the heated oxygen sensor on bank one. As we said earlier, it can go bad because of contamination. 

So, first of all, check the O2 sensor to see if it is contaminated and clean it with a contamination cleaner if it is. Then, check the voltage coming out from the sensor using a voltmeter. 

The voltage reading will fluctuate between 0.1 and 0.9 volts. If the sensor is too late to start fluctuating or the reading is so high or low then the range is required, then the O2 sensor has become faulty. So, replace the sensor to solve the code P0038 on your Jeep vehicle.

On average, it will cost between $150 and $470 to replace a bad oxygen sensor bank 1 sensor 2. The labor cost can be between $100 and $130, while a new oxygen sensor can cost around $20 to $298.

5. Checking the ECM:

If all the tests you have already done have found no fault but the code P0038 is still appearing, you may need to replace the ECM. From this, you can be pretty sure that your ECM is bad. 

But if you want to test the ECM itself, you should hand over the job to a professional, as it requires specific knowledge and software. 

Replacing a bad ECM is pretty costly. In general, it will cost between $400 and $1200. 

The labor is expected to be around $75-$100, while a new ECM may cost between $325 and $800. The price of the ECM can also increase depending on your car’s model.

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Are you eager to know more about the code P0038 on Jeep vehicles? Don’t worry! Here are the answers to some FAQs about the DTC P0038:

Can you drive a Jeep with the P0038 code?

Yes, generally you can drive cheaply with the P0038 code. But driving for too long without fixing this code can cause more acute damage to the car. For example, it can damage the catalytic converter. 

How much does it cost to fix the Jeep P0038 code?

The average cost of fixing the Jeep code P0038 is between $75-$155. Labor cost is estimated between $55 and $100, while the parts will cost around $20-$100. But it can also be more, depending on the car’s model, location, and mechanic. 

How serious is the code P0038 on my Jeep?

The P0038 code is moderately severe to severe, like other car problems. It will illuminate the check engine light and cause poor engine performance and decreased fuel economy. In most cases, it affects the performance of catalytic converters. 


Experiencing the code P0038 on your Jeep is very common. However, it’s necessary to fix the code as early as possible to prevent further damage. 

It is also pretty simple to fix this trouble code on Jeep and typically it will take less than one hour to be done. Therefore, you should not take too much time to eliminate the code.

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