P00B7 Chevy Cruze – Symptoms, Causes, and Detailed Troubleshooting Steps

Chevrolet Cruze owners may be experiencing issues with their vehicle’s performance, including stalling, poor mileage, and a loss of power. One potential cause of these problems is a P00B7 code that may indicate a problem with the engine coolant flow.

If your Chevy is popping up P00B7, it is important to deeply understand its meaning, symptoms, and diagnostic steps. Dive in!

What Does P00B7 Code Mean?

P00B7 occurs whenever PCM notices any sort of discrepancy between the RCT sensor and ECT sensor. Thus, the PCM will indicate that there is a coolant flow restriction.

Let us dig in a little deeper.

ECT comprises a resistor. This resistor is thermally sensitive and is entirely covered by resin. Further, it has a metal casing. This casing is usually made up of brass as it has exceptional durability. The ECT sensor is screwed in the paths of engine coolant, may it be intake manifold or block. For this reason, it is usually threaded.

As soon as the coolant starts flowing across the sensor, the thermal resistance drastically reduces. This happens when the coolants warm out a bit. A decrease in resistance causes a subsequent increase in sensor voltage.

However, when the engine’s temperature is lowered, the opposite happens. The sensor shows enhanced resistance and decreased voltage. PCM examines these changes in voltages corresponding to the coolant temperatures.

One coolant temperature reading is from the RCT sensor, while the other is detected by PCM. These two readings need to differ only by a certain allowable parameter. If it exceeds that value, this error code is stored.

Meaning of P00B7 Chevy Cruze Code

Before explaining the code in detail, you need to grasp what the following means.

ECT Sensor: ECT Sensor is responsible for reading the engine coolant temperature and sending that information to the powertrain control module. By doing so, the powertrain control module can optimize things like fuel delivery and ignition timing.

RCT Sensor: The radiator coolant temperature sensor is responsible for sending information to the engine control unit (ECU) about the temperature of the coolant. This information is used to control the fan speed, as well as other systems in the vehicle that are related to engine cooling. A working radiator coolant temperature sensor is essential for keeping the engine running at its optimal temperature.

PCM: A power control module is responsible for regulating engine coolant temperature. It uses various sensors to determine how much power the engine needs to run efficiently. The power control module is also responsible for charging the battery and keeping it running at optimum levels.

If the engine gets too hot, the power control module will reduce the engine’s power to keep it from overheating. This can help prevent damage to the engine, and it can also help improve fuel economy by reducing drag on the engine.

Do You Need to Worry About P00B7 Chevy Cruze?

A P00B7 is a code that can disturb fuel delivery. Furthermore, it can also affect the vehicle’s ignition timing. It can lead to poor fuel economy, ultimately causing severe problems. Thus, this code needs to be dealt with with urgency. It is a critical one and shouldn’t be ignored.

P00B7 Chevy Cruze- Common Symptoms You Will Experience

You will experience multiple symptoms corresponding to P00B7 in your Chevy Cruze. It is wise to be aware of them.

Rich Exhaust

When a car has a rich exhaust, it means that there is too much fuel in the air-fuel mixture. If you are noticing one or more of the following symptoms, your vehicle probably has a rich exhaust.

  • The engine runs rough or stalls.
  • The engine smokes black or blue.
  • You hear knocking or pinging noises.
  • The car doesn’t accelerate as well as it should.

Driveability Issues

Drivability issues can be frustrating and dangerous. Symptoms of a drivability issue can vary, but some common ones are stalling, sputtering, hesitation, and rough running.

Rough Idling

One of the most common symptoms of the P00B7 code is rough idling. This can cause the engine to stall or run rough. You may also notice a decrease in fuel economy and an increase in emissions.

Reduced Fuel Economy

Reduced fuel economy is a common symptom of a p00b7 code. This code results in more fuel consumption of the engine, reducing the DTE.

Leading Causes of P00B7 Code

P00B7 is a trouble code that indicates an error with the coolant temperature. There are many potential causes of this problem, and depending on the severity, it may require a repair or replacement of the PCM. Plunge in to know all the causes and how to diagnose them.

Low Coolant Level

If any of your car’s “check engine” or “check gauge” lights come on, and you get the code P00B7, it means that the coolant level is low. The car’s computer is telling you to add more coolant to the system.

There are several reasons why the coolant level might be low.

  • One reason is that there might be a leak in the cooling system.
  • Another possible cause of a low coolant level is when the radiator cap isn’t tightened properly.
  • A third possibility is that the thermostat might not be opening all the way.


In order to diagnose if the coolant level is low, you need to check the coolant reservoir.

Stuck Thermostat

The thermostat is designed to open and allow coolant to flow through the engine when the car gets too hot. If it’s stuck open, your car’s engine will never reach the correct temperature, and you’ll have problems with cooling and heating. When the coolant level falls too low, it can cause the thermostat to stick open.


  • To diagnose if this is the problem, try turning off the power to the thermostat for a few minutes and then turning it back on.
  • If it starts working again, then you know the thermostat was stuck.

Faulty ECT Sensor

If the ECT sensor fails, it can cause a low coolant level indication on the dash. This is because it will not send the correct information to PCM, which will then control the fans and radiator opening/closing.


  • The first step in detecting a faulty ECT sensor is to check the wiring harness.
  • Make sure that all of the connections are secure and there is no damage to the wiring.
  • If everything looks good, then check the sensor itself.
  • Remove it from the engine and take a look at it closely.
  • Check for any signs of damage or corrosion.

Defective RCT Sensor

One common issue with the coolant system is a defective RCT sensor. This sensor helps monitor the temperature of the coolant in the system. If it goes bad, it can detect faulty coolant temperature, causing the warning light to come on.


Diagnosing a defective RCT sensor includes checking an engine light that stays on, overheating, a loss of power, and poor fuel economy.

Shorted Connectors

One of the most common causes of P00B7 is a short in the connector. This can be caused by a number of factors, including corrosion, dirt, or damage to the connector. When this happens, it can prevent coolant from flowing properly and cause the engine to overheat.


To diagnose shorted connectors, you have to do multiple checks.

  • The first thing you should do is check the battery. You can test the battery by using a voltmeter.
  • The next thing you should check is the starter. You can test the starter by trying to start the car in neutral. If it starts, then the starter is bad and needs to be replaced.
  • The last thing you should check is the ignition switch.

Faulty PCM

If you’re experiencing low coolant warnings or even engine overheating, it’s possible that the PCM (powertrain control module) is to blame. The P00B7 code indicates a fault in the PCM’s ability to properly manage the engine coolant system.

In some cases, this can be caused by a faulty sensor or circuit. If the problem is with the PCM itself, then it will need to be replaced.


If your car is experiencing any of the following problems, it may be due to a faulty PCM:

  • Your car won’t start.
  • The engine is misfiring.
  • The check engine light is on.
  • There are strange noises coming from the engine.
  • The car is not accelerating, or its acceleration is abnormal.

Fixing the P00B7 Diagnostic Code- The Ultimate Solution

P00B7 code can be critical. It can lead to the malfunctioning of the vehicle. To fix this, you first need to diagnose the issue. Once you know where the problem is, you can check the manual to apply the relevant fix. Below are the most effective fixes for the P00B7 code.

  • Replacing the RCT sensor
  • Changing ECT sensor
  • Replacing PCM
  • Connecting the wires properly
  • Adding more coolant

How To Prevent P00B7 From Showing Up Again?

You sure do not want to go through all the diagnoses again, right? Thus, it is important to keep a regular check on your vehicle. To keep off this code from coming on again, you should

  • Keep the coolant level optimal
  • Make sure that all the connections are tightened
  • Check to check the thermostat