P0635 OBD-II Trouble Code: Power Steering Control Circuit

check engine light

P0635 code definition

The P0635 code refers to a detected problem with the vehicle's power steering control circuit. This malfunction has been detected by the Powertrain Control Module (PCM) or another one of the control modules linked up to the power steering control circuit.

What the P0635 code means

If one of the pertinent control modules registers a problem with the power steering control circuit, the P0635 trouble code will be logged in the vehicle's onboard computer. This may result in a host of steering issues for the vehicle in question.

What causes the P0635 code?

In many cases, a P0635 trouble code is the result of a faulty steering position or pressure switch. Although faulty switches can account for the majority of this code, faulty, corroded and broken wiring related to the control modules is also known as a potential case.

What are the symptoms of the P0635 code?

The P0635 will typically result in steering problems. The vehicle may steer erratically, and the steering wheel may react stiffly. A logged P0635 trouble code and illuminated engine lamp will accompany this issue for the sake of diagnosis.

How does a mechanic diagnose the P0635 code?

A mechanic may first diagnose a P0635 by reading the code with an OBD-II code reader. Firstly, the position and pressure switches in the steering system should be checked for potential signs of faultiness or malfunction. Each control module relating to the steering circuit should be tested for voltage and visible signs of malfunction. Because there are so many control modules potentially associated with the steering circuit, you should focus first on the modules your vehicle may have had issues with in the past.

Common mistakes when diagnosing the P0635 code

Because the P0635 relates to a control module's failure to communicate properly, other trouble codes may be logged and repaired needlessly. If you have received multiple trouble codes, you should focus on the ones that pertain directly to the Controller Area Network (CAN) before tending to component-related issues themselves. Referring to the order in which the OBD-II code reader reports the trouble codes may also help in distinguishing the root causes from their results. A specialized scanner (such as an Autohex) should be used to pinpoint control module issues more quickly and accurately.

How serious is the P0635 code?

A P0635 will limit your vehicle's drivability if left unchecked. Although your vehicle may still be drivable, limited steering can prove to be a safety hazard on the road. With that in mind, a P0635 code should be addressed as soon as possible.

What repairs can fix the P0635 code?

If one of the steering switches has been identified as damaged or faulty, it should be replaced as needed. Any faulty, corroded, damaged or broken wiring related to the steering system should be fixed as well. If any of the control modules have been identified as problematic, a memory saver should be attached to the system in order to save the info from being potentially wiped. If all of the pertinent components and wiring have been verified or repaired, you should scan it again with an OBD-II scanner to see if the computer still reads the P0635 code. Give the vehicle a test drive following your repairs to see if the code returns.

Additional comments for consideration regarding the P0635 code

Many vehicle models require the steering malfunction to be recorded in a consecutive series of driving cycles in order for the trouble code to be logged.

Need help with a P0635 code?

YourMechanic offers certified mobile mechanics who will come to your home or office to diagnose and repair your vehicle. Get a quote and book an appointment online or speak to a service advisor at 1-800-701-6230.

The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

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