What is the P0546 fault number? What is the Exhaust Gas Temperature Sensor Circuit High (Bank 1, Sensor 1) description? How do I fix the P0546 fault code What are the causes and symptoms of the P0546 error code?
What is the P0546 fault code? What does it signify?
A P0546 code indicates that the powertrain controller module (PCM), has detected an error in the exhaust temperature (EGT), sensor circuit. If the voltage signal coming from the exhaust gas temperature sensor into the PCM exceeds limits set by vehicle manufacturers, then fault code P0546 will trigger and the check engine lamp will turn on.
“Bank 1” In the code description, refers to the engine row with the cylinder 1 and “Sensor 1” This refers to “up” EGT sensor placed in front the catalytic conversion. The EGT sensor is located between gasoline vehicles’ exhaust manifolds and the catalytic convert in diesel vehicles. It is usually near the turbo exhaust inlet for turbo vehicles.
As the name implies, the EGT sensor measures the exhaust gas temperature to protect the catalytic convert from excess heat. It is used in almost all new generation gasoline and diesel engine vehicles. It is made up of a heat-sensitive resistor that transmits exhaust heat to the PCM and converts it to an electrical voltage. There are usually two cables. One wire is used as ground and the other to receive the 5 volt reference from the PCM. The grounding resistance decreases with increasing exhaust gas temperatures, and vice versa. The PCM will adjust the engine timing or fuel ratio if it detects an excessive voltage signal from the exhaust temperature sensor. This is done to restore the catalytic converter to its normal range. The data from the EGT sensor can also be used to determine DPF renewal in diesel vehicles.
P0546 fault codes are found in vehicles made by Nissan, Subaru and Lexus as well as Volkswagen, Mercedes-Benz.
What causes the P0546 Fault code?
Fault code P0546 can be triggered by the following common causes:
- – Broken, damaged, melted, or corroded wires, and/or loose, corrosioned connectors to EGT sensor
- – Short Circuit in ground wire between EGT sensor and the PCM
- Pressure problems can be caused by improper exhaust application, sub-industry use or poor quality components
- – Excessive exhaust leakage at the sensor’s intake
- – Defective EGT sensor (Bank 1, Sensor 1)
What are the symptoms for P0546 fault code?
You may experience the following symptoms if your vehicle has the code P0546:
- – Turn on the engine light (often without other symptoms).
How to Fix the P0546 Fault Code
First, inspect the exhaust gas temperature sensor as well as all circuits. The sensor should be removed from the circuit board and checked for damage with a digital resistance tester. An EGT sensor should have a resistance of around 150 ohms. Replace the sensor if it has a resistance lower than 50 ohms.
The sensor can be heated with a hair dryer, heat gun, or heat gun. An ohmmeter will monitor the temperature. As the sensor heats up, its resistance should decrease and then increase as it cools down. A sensor that is not working properly should be replaced.
This is the biggest mistake in repairing the code. It is not a good idea to replace the oxygen sensor. This will not solve the malfunction code.
The following repairs may be able to resolve the P0546 fault code:
- – Repair and replacement of short or open circuit cables or connectors that are damaged, melted, or corroded to the EGT sensor
- – Fixing ground wire issues in EGT sensors
- – Test and replacement of the EGT sensor if necessary
- – Repair of exhaust system leaks
- – Reprogramming or replacement of a faulty PCM
How serious is the P0546 fault code?
While P0546 doesn’t interfere with vehicle operation or make it unsafe, it can cause voltage and other problems. This is because the PCM relies upon the sensor to deliver optimal functions. The code can cause exhaust system overheating and damage to the catalytic converter if it is not followed. This can lead to much higher repair costs.
