AutoLogicTools

OBD-II trouble code

U0435: Invalid Data Received From Power Steering Control Module (Rear)

A module is receiving messages from the rear power steering control module, but the data inside them is implausible or out of range. The link is alive — the content is wrong. Can reduce or disable rear steering assist.

Quick facts

System
Network
Category
Network Communication
Severity
Medium severity
Drivable
Usually safe to drive short-term
Repair cost range
$100$1,400
DIY difficulty
Shop recommended

What does U0435 mean?

The rear power steering control module runs the electric power steering (EPS) assist for the rear axle on vehicles with four-wheel or rear-wheel steering. It reads steering-angle, vehicle-speed, and torque inputs and commands the rear steering actuator, then reports its status to other modules over the network. U0435 sets when a receiving module is still hearing from the rear power steering module, but the data in its messages is invalid: a value is out of range, implausible, or contradicts what other modules see. The link is alive; the content can't be trusted. That is the key difference from a lost-communication code, which means the module has gone completely silent. This is the rear-axle counterpart to U0420, which covers the primary (front) power steering control module.

Because the fault is bad data rather than a dead bus, the causes cluster around whatever makes the module broadcast wrong information. A failing input — the rear steering-angle or position sensor, or the torque/feedback sensors — can push the module into reporting implausible values. Low system voltage is a classic trigger, since EPS modules draw significant current and their logic gets unreliable as voltage sags. The module's own software can be at fault if it is outdated, corrupted, or was never properly programmed after a replacement, and corroded connectors or chafed wiring near the rear subframe can corrupt otherwise-good messages in transit. A failing rear steering actuator motor can also make its feedback data implausible.

Symptoms are steering-related but usually confined to the rear-steer function. You may see a check engine light plus a steering or chassis warning, heavier or less precise low-speed maneuvering, a wider turning circle if rear steer disables, or a message that the four-wheel-steering system is unavailable. The vehicle stays driveable because the front power steering and base steering geometry continue to work — the car simply loses the rear-steer assist that sharpens low-speed agility and high-speed stability — which is why U0435 is medium rather than high severity. Still, changed steering feel matters, so get it diagnosed. Because U0435 is frequently a secondary code, read the full list — a companion steering-angle or actuator code often names the real root cause.

Common causes

  • Failing rear steering-angle or position sensor feeding bad data
  • Faulty rear steering actuator motor or its feedback reporting implausible values
  • Low system voltage or a weak battery/charging system
  • Corroded connectors or chafed wiring near the rear subframe
  • Outdated, corrupted, or mismatched rear power steering module software
  • Rear power steering module replaced without proper programming
  • Rear power steering control module internal fault

Symptoms

  • Check engine light with a steering or chassis warning
  • Heavier or less precise low-speed maneuvering
  • Wider turning circle if rear steering disables
  • Message that four-wheel steering is unavailable
  • Companion steering-angle or actuator codes stored alongside U0435
  • Vehicle driveable with front and base steering unaffected

Diagnostic steps

  1. 1.Read ALL stored codes first — U0435 is often secondary to a steering-angle or actuator code that names the bad signal.
  2. 2.Confirm the vehicle is equipped with rear/four-wheel steering and locate the rear steering module.
  3. 3.Check battery and charging system voltage; low voltage causes implausible EPS module data.
  4. 4.Use live data to compare the module's reported rear steering angle and actuator feedback against actual conditions.
  5. 5.Inspect rear-subframe wiring and connectors to the module and actuator for corrosion and damage.
  6. 6.Verify the module has the correct, current calibration, then address companion codes before condemning the module.

Repair cost

$100$1,400

Cost depends on what is producing the bad data. A rear steering-angle or position sensor is typically $150-$400 installed. Correcting low voltage varies. A rear steering actuator is the expensive item at $600-$1,400 depending on the vehicle. A module reflash is $100-$300, and rear power steering module replacement with programming runs $500-$1,100 — but that should only follow thorough diagnosis, since U0435 is frequently a secondary code.

Estimate your repair

Run the numbers for your vehicle

Open the Repair Cost Estimator with module communication / can bus diagnosis preselected. Adjust labor rate and vehicle category to fit your situation.

DIY vs shop

Leave this one to a qualified shop. It typically involves emissions-critical components, refrigerant handling, or other work that requires manufacturer-grade tooling, training, or certification. DIY attempts often produce a more expensive problem than the original code.

Related codes

Frequently asked questions

What does the rear power steering control module do?

On vehicles with four-wheel or rear-wheel steering, it runs the electric assist for the rear axle. At low speed it steers the rear wheels slightly opposite the fronts to tighten the turning circle, and at high speed it steers them slightly with the fronts for more stable lane changes. U0435 is the rear-axle counterpart to U0420, which covers the front power steering module.

Is U0435 safe to drive with?

Generally yes in the short term. The front power steering and base steering geometry keep working, so the car remains driveable — it just loses the rear-steer assist, which makes low-speed maneuvers take a bit more wheel and widens the turning circle. Drive with the changed feel in mind and get it diagnosed rather than ignoring it.

How is U0435 different from a lost-communication code?

A lost-communication code means the rear power steering module has gone silent. U0435 means it is still talking, but the values in its messages are implausible or out of range, so the receiving module rejects them. Lost communication points toward power, ground, or bus wiring; U0435 points more toward a bad sensor input, an actuator fault, low voltage, or software.

Should I replace the module for U0435?

Only after diagnosis confirms it, which is not the most common cause. The module depends on sensors and an actuator, so a failing rear steering-angle sensor, low voltage, or corroded wiring can produce the same code for less money. A replacement module also needs programming and calibration, or it can set the same code again.

AutoLogicTools provides general automotive planning information. Trouble code interpretations, repair cost ranges, and DIY guidance vary by vehicle, model year, location, parts quality, and shop labor rate. Always verify a diagnosis with a scan tool and a qualified automotive professional before approving repairs.