P2656 - OBD Trouble Code

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Confused? Here’s all you need to know about this code. The OBD-II code reduced engine performance is described as a “A” rocker arm actuator system performance/stuck off. Variable valve technology is used by the newer vehicles to enable greater airflow through the engine at higher RPMs. This enhances and allows better performance over a wider range.

A number of manufacturers are upgrading to a variable valve lift system that allows the valve to open by a wider margin. The code P2656 is set in case the solenoid inside the assembly fails. The position sensors are located inside the variable lift rocker arm assembly. This helps the engine computer (PCM) control the operations of the assembly.

What causes this problem with the Rocker Arm Actuator System Performance/Stuck Off Bank 2?

• Faulty engine oil type
• Defect in the ‘A’ rocker arm actuator
• ‘A’ rocker arm actuator harness is loose or burnt
• ‘A’ rocker arm actuator circuit powerless electrical connection
• Engine oil is either less or overfilled

1. Engine Oil - Excessive mileage? Check engine light or oil change light? Then this is indicative of contaminated engine oil. We advise you to replace or restore it immediately to overcome the problems caused by the error code P2656.
2. Rocker Arm - A distorted rocker arm can end up being the chief host inviting the error code P2656. In addition to this, this may lead to diminishing engine performance too. So replacing one can be one of the wisest decisions to avoid a problematic system.
3. Rocker Arm Position Sensor - A defective rocker arm position sensor can worsen the way the engine idles, or the acceleration behaviour. It is recommended to get it changed or repaired immediately to avoid further problems.
4. Powertrain Control Module - It should be noted that the powertrain control module is often regarded as the brain of the system. A fault in the powertrain control module is likely to trigger problems with the engine such as a sluggish engine crank, rough idle and illuminated malfunction indicator light. Now you can simply overcome the problems caused by the error code by logging into Parts Avatar for your new PCM.
5. Rocker Arm Solenoid - Get your error code P2656 fixed immediately by just replacing or repairing the rocker arm solenoid. Now you can get it delivered right at your doorstep with Parts Avatar. Order now!

For us our customers are everything, and that’s why we will help you to diagnose P2656 code by mentioning some important symptoms below:

Common Symptoms

• Reduced engine performance
• Increase in fuel consumption

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 few common steps to correct this issue with your vehicle’s:

• Replace or repair your damaged ‘A’ rocker arm actuator immediately
• Amendments should be performed to fix a bad ‘A’ rocker arm actuator circuit
• Check the engine oil type present in the system along with the quantity levels. Make changes accordingly
• All the corroded harness in the ‘A’ rocker arm actuator should be mended or restored

Apart from this, you might need to replace other damaged parts too like solenoid, rocker arm, powertrain control module, overfilling engine oil, position sensors and more. You can easily find all these parts with us. Not only that you can get these parts shipped to your door free, if your cart value happens to exceed $99.

Here are some steps which you should follow in order to diagnose this fault code:

• Electromagnetic sensors control crankshaft and camshaft positions.
• The relief holes in crankshaft and camshaft drive gears are used by these sensors to provide signal interruptions of the electromagnetic field.
• The PCM displays the interruptions in the electromagnetic field as square waveform patterns, which represent different degrees of voltage.
• Electromagnetic resistance in the 5-volt circuit is used to create these variations in voltage.
• Some manufacturers use numerous crankshaft sensors to feed separate data streams to the PCM.
• Generally, the input for engine ignition and fuel injection timing is provided by these data streams.
• Engines that have numerous camshafts generally use a camshaft sensor for each camshaft.
• To interrupt the electromagnetic field, other automakers utilize notches cut into shafts or nodules that are permanently attached for this reason.
• Depending upon the sensor placement, these notches are generally placed near the rear or center of the shaft.
• The manufacturer, at times, can even place the transmission bell-housing below the crankshaft sensor and reads crankshaft position from interrupter holes in the flex plate.
• The first step for a proper diagnosis is making sure that all engine timing indicators are properly aligned.
• The next step in the process of diagnosis is testing belt, chain deflection using manufacturer’s requirements.
• If timing components prove to be in good working condition and properly aligned, the next step would be testing VVT or VCT solenoids ad circuitry.
• In rare cases, there may be PCM or sensor failure.
• Sensors are less susceptible to fail than electrical wiring and connectors, especially where oil or other corrosive fluids are concerned. For the successful diagnosis of this code, several tools will be necessary.
• For performing a successful diagnosis you should have access to a suitable OBD-II scanner (or code reader), a digital volt/ohmmeter, and an oscilloscope.
• A manufacturer’s service manual (or the equivalent) will also be required.
• Inspect all wiring and connectors visually.
• Repair or change damaged, defective, shorted, or burnt wiring, components, an connectors as required.
• After repairs are completed, it is important to retest the system to ensure success. If all system including wiring, connectors, and components (including fuses) seem to be in normal working order, connect the scanner (or code reader) to the diagnostic connector and record all stored codes and freeze frame data.
• The intermittent conditions that may have caused this code to get stored can be diagnosed using this information.
• Proceed by clearing the code and operating the vehicle to see if it returns.
• This step will confirm whether or not the malfunction is intermittent.
• Test drive the vehicle after the codes are cleared to check incase the code returns.
• Failure of the code to immediately return indicates that an intermittent condition.
• It may prove quite difficult to diagnose intermittent conditions and in extreme cases may have to be allowed to become worse before an accurate diagnosis can be made. Once the connector has been disconnected from the affected sensor, check for a reference voltage signal (usually 5-volts) and a ground at the connector end (key on/engine off)
• If reference voltage and/or ground are not detected, the connector needs to be disconnected from the PCM and all circuits are tested for resistance and continuity.
• Refer to the manufacturer’s service manual for wiring diagrams, technical service bulletins, and/or flow charts that may be useful.
• Mend or replace the circuits, connectors, or components that do not comply with manufacturer’s requirements, as suitable.
• After the required repairs have been made, clear codes and test drive the vehicle to ensure that your repair has been successful.
• Check for any casualties or defects in the waveform and replace the sensor if present.
• Once the the repairs have been made, clear the codes and test drive the vehicle to make sure that your repairs have been successful. If reference voltage and ground signals are present, relink the sensor and use the oscilloscope to regulate live data waveform patterns. Normal wave for patterns indicate a faulty PCM.
• An important thing to remember is that PCM failure is rare and replacement will require reprogramming
• Camshaft and crankshaft sensor replacement would be required in some applications in sets.
• Refer to your service manual for specific instructions.
• One manufacturer even places the crankshaft sensor on top of the transmission bell-housing and reads crankshaft position from interrupter holes in the flex plate.
• After repairs are made, clear codes and test drive the vehicle to ensure that your repair has been successful. If reference voltage and ground signals are present, reconnect the sensor and use the oscilloscope to monitor live data waveform patterns.

Common Mistakes When Diagnosing the P2656 Code

• Here we have listed a few common mistakes:
• Failure of powertrain control module (PCM)
• Damaged variable valve lift controller assembly
• Wiring problem