Turbocharger Electric Actuator Stepper Motor Fault Codes – Part 1
What if you get a fault code thrown by the ECU, for the Turbocharger Electronic Actuator Stepper Motor?
It’s worth clearing the fault code first, to see if the code comes back again.
If the Turbocharger Electric Actuator Stepper Motor Fault Code persists, read on.
What are the Common Stepper Motors Fault Codes?
P004C: Turbocharger/Supercharger boost control ‘B’ circuit low.
With this code, it’s a good idea to check resistance across the actuator to see if it has an open circuit.
An open circuit (current not able to flow through), usually means the stepper motor actuator will need to be replaced.
If you’ve run the vehicle through deep water recently, this could create such a problem.
P2563: OBD-II generic code.
This code indicates an issue detected in control of variable vane geometry. So, this could mean performance is out of range, or the position sensor is not within spec.
Essentially, the actuator has detected incorrect vane positioning for a specified amount of turbocharger boost.
Causes of the P2363 Fault Code:
- This code could show the variable vanes are jammed (usually through excessive carbon build-up in the vanes and associated VNT assembly).
Incidentally, this is why upon installation of a new turbo, the engine exhaust manifold should be thoroughly cleaned.
Incorrect combustion due to issues such as injector seal problems, cause excess ‘soot’ to be pushed through the exhaust system and through the VNT assembly. - Alternately, it could be associated with a defective electric actuator boost sensor.
Symptoms of the P2363 Fault Code include:
- Low boost giving lack of power especially when the vehicle is under load or during acceleration.
- The ECU forces the engine into ‘limp mode’ as a way of protecting the engine and components (such as turbocharger), from further damage.
Diagnosis of the P2363 Fault Code
It is a good idea to check the vanes and assembly first. Check by removing the actuator arm from the lever on the side of the turbo’s turbine housing, moving the lever side-to-side.
The lever should move freely through full range with little resistance.
If there is moderate resistance through the entire range or incomplete movement, it may be remedied with the turbo in-situ.
This is achieved by hooking the vehicle to a specialized soot cleaning machine.
The machines are capable of running a solution through the engine that breaks down carbonized build-up, expelling build-up as vapor only.
It will clean from the beginning of the induction system, to the tip of the exhaust.
Unfortunately these machines are not found everywhere, are expensive, and can take 4 hours to run the full cleaning cycle.
But there are off the shelf aerosols that can do the job, albeit in a much less thorough way.
Also, they may not fix a turbocharger VNT assembly that is heavily ‘coked’ or carbonized, and hence completely jammed.
The root cause of the excessive çoking should be found and remediated.
In such cases, it is best to remove the turbo and clean the manifold and EGR Valve, and check flow through the DPF.
Then replace the turbocharger if the VNT assembly is heavily jammed.
Rebuilding the turbocharger and vane assembly is an option, but will cost more than one of our new Aftermarket Turbochargers.
With a new Turbocharger, you will also benefit from our exclusive 3 Year Warranty, as opposed to the 3 or 6 months usually given on rebuilt turbos.
If the fault is not due to the above issues, check the stepper motor actuator wiring harness and plugs for broken or shorting circuits.
But if none of the above problems are present, a replacement Electric Actuator Stepper Motor may fix the issue.
And once the issue is deemed as resolved, clear the ECU fault code and retest to affirm problem resolution.
P0046: OBD-II generic code.
This fault code is thrown by the ECU for Turbocharger Boost Control Valve/Solenoid/Motor Circuit Range/Performance.
Manufacturers have a variety of definitions for this fault code. But most commonly, it’s associated with an out of range reading in the turbocharger boost-control circuit.
And usually shown as: ‘P0046 Turbo/Supercharger Boost Control ‘A’ Circuit Range Performance’
The “A” indicates the problem within a portion of the system circuit, instead of an exact symptom or component.
Causes of the P0046 Fault Code:
- Water ingress into the Turbocharger Electric Actuator Stepper Motor due to a deep-water crossing, or pressure cleaning of the engine bay.
- Leaks or loose connections in the air-intake manifold.
- Leaking gaskets at exhaust manifold.
- Restrictive airflow through air filter.
- Jammed variable vanes / wastegate.
- Faulty boost detection by sensor.
- Open circuit or shorting wires in the boost sensor circuit.
Symptoms of the P0046 Fault Code include:
- Most commonly, a normal idle but little to no boost, with loss of power during acceleration.
- The ECU forces the engine into ‘limp mode’ as a way of protecting the engine and components, such as turbocharger from further damage.
Diagnosis of the P0046 Fault Code
First, check the wiring to and from the boost sensor for damage and loose connections.
Then inspect the Turbocharger and sub-systems for air or vacuum leaks at hoses, flanges and gaskets.
And what if your vehicle has a pneumatic vacuum (mechanical) actuator and is a variable vane turbocharger(VNT)?
Also check that the wastegate solenoid valve is operating correctly. If not, just try replace that component first.
If all looks ok, run a test on boost-pressure whilst the vehicle is running at usual operational speeds.
Factory boost pressure for unmodified turbochargers range from around 9 – 12 PSI.
Boost pressure should not significantly spike (over-boosting), nor drop quickly.
Finally, check the operation of the variable vanes as described above in “Diagnosis of the P2363 Fault Code”.
And if none of the above Turbocharger Electric Actuator Stepper Motor Fault Codes are present, a replacement Actuator may fix the issue.
And once the issue is deemed as resolved, clear the ECU fault code and retest to affirm problem resolution.
You will also find more Electronic Actuator Problem Codes here.
If you find that you require a replacement Turbocharger Electric Actuator Stepper Motor, we stock a range of aftermarket products extremely affordable prices, all with our exclusive 36 Month Warranty.
And if you have any other query on matching turbo parts for your vehicle, please feel free to contact our sales support on: 0490 059 316.