Error Code P04A5: What It Means & What To Do?

<<See All OBD Codes

Experiencing problems with your exhaust pressure sensor like burnt wires, immovable sensor, or anything else? Then it’s more likely that you are experiencing the error code P04A5. OBD-II Code Powertrain Control Module (PCM) failure is explained as an Exhaust Pressure Control Valve "B" Stuck Closed

The Exhaust Pressure Control Valve operates the exhaust back pressure as the engine warms up. If the engine control module (PCM) identifies an incorrect signal from the Exhaust Pressure Control Valve, the PCM will show up the P04A5 code.

Exhaust Back Pressure Regulator valve manages the exhaust back pressure during cold ambient temperatures so as to increase the cab heat and minimize the time that is needed to defrost the windshield. The Engine Control Module (ECM) uses the calculated exhaust back pressure, (ambient) intake air temperature, engine oil temperature and engine load so as to decide the expected exhaust back pressure. Valve position is managed by turning the output signal circuit to 12 volts present inside the ECM. Change the on/Off time from 0 to 99 % based on the exhaust back pressure preferred. On each initial engine start-up, the exhaust back pressure valve is exercised by the ECM which commands it to cycle on and off once. On start-up, if the temperature of intake air that is sensed by the Intake Air Temperature (IAT) sensor is < 37°F (5°C) and the temperature of the oil sensed by the Engine Oil Temperature (EOT) sensor is between 32°-140°F (0-60°C) it will remain to keep the back-pressure valve partly closed. As the temperature of oil increases during engine operation, the ECM will control the valve in reaction to the growing oil temperature.

What causes this problem with the Exhaust Pressure Control Valve "B" Stuck Closed

• Faulty exhaust back pressure control valve position sensor
• Jammed exhaust pressure sensor
• Damaged exhaust pressure control valve
• Open or burnt wiring in one of the exhaust pressure control valve circuits

1. Powertrain Control Module - Are you looking for the right replacement part for your vehicle? Parts Avatar has parts for every vehicle make at the best prices online.
2. Exhaust Pressure Control Valve - If you come across any leaky area in your exhaust pressure control valve, repair it instantly.
3. Exhaust Pressure Sensor - One of the reasons for this error code, is due to a leak in the exhaust pressure sensor. Get them repaired.
4. Engine Control Module - A faulty engine module can collapse the working system. Replace them with new ones from Parts Avatar.

For us our customers are everything, and that’s why we will help you to diagnose P04A5 code by mentioning some important symptoms below:

Common Symptoms

• Highly reduced engine performance
• Overheat of Engine or transmission
• Exhaust glowing red hot after driving
• Extra exhaust back pressure codes

After you know the symptoms of your vehicle’s problem, it becomes easy to detect it and get started with solving it. So, next on our list is a few common steps to correct this issue with your vehicles’

• Damaged Powertrain Control Module
• Fault in the Engine Control Module
• Leaky Exhaust Pressure control valve
• Leakage in the Exhaust Pressure Sensor

To do all this, you will need few high-quality auto parts such as Powertrain Control Module, Exhaust Pressure Control Valve, Exhaust Pressure Sensor, and Engine Control Module and so on. From where will you get them? From your local store? Well, why go there when you can order quality parts with us while sitting in the comfort of your home. So, just browse through our website and order your needed parts today.

If you want to easily diagnose this P04A5 fault code, then all you have to do is to follow the steps which are mentioned below:

You will require a reliable vehicle information source to diagnose a code P04A5. Other tools needed:

• Diagnostic scanner.
• Digital volt/ohm meter (DVOM).
• An infrared thermometer along with a laser pointer.
• After a cautious inspection of system wiring and connectors, find the diagnostic port of the vehicle. Join the scanner to the port and recover all stored codes and freeze frame data. Write this info down as it may be helpful when your diagnosis proceeds.
• Now, clear the coding and test drive the vehicle to see if the P04A5 error returns instantly. If you come across intake air temperature codes or engine coolant temperature codes, analyze and mend those before trying to diagnose the P04A5.
• Search technical service bulletins (TSB), which is applicable for the vehicle, codes, and symptoms in question. If you find anyone that is likely, it will be helpful in your diagnosis.
• If there are no wire or connector issues found, start by testing the normal voltage signal at the exhaust pressure control valve (with the DVOM). You may use the scanner to initiate a cold start condition and stimulate the exhaust pressure control system.
• If the applicable voltage/ground signal is not found at the exhaust pressure control valve connector, separate all related controllers and use the DVOM to test single circuit resistance and stability. Circuits that are non-compliant have to be fixed or changed.
• If the exact degree of voltage/ground is exposed at the exhaust pressure control valve, then follow the manufacturer’s suggestions for testing the exhaust pressure control valve (using the DVOM). If the exhaust pressure control valve pin out test is not equivalent to manufacturer’s terms, it should be changed. If the exhaust pressure control valve and circuits are curable, test the exhaust pressure control valve position sensor and the exhaust pressure sensor according to manufacturer’s recommendations. Exchange the faulty components as necessary.
• You can use the infrared thermometer to increase an actual exhaust temperature reading if there is no scanner data display available. This could prove supportive to define whether the exhaust pressure control valve is functioning or not. It can also detect a valve that is jammed is either open or closed.
• An imperfect catalytic converter or muffler will not allow a code P04A5 to be stored.
• Exhaust pressure control systems are often used in turbocharged or supercharged applications.

Common Mistakes When Diagnosing the P04A5 Code

• A failed Exhaust pressure control valve
• Damaged Powertrain Control Module
• Wiring problem