01/09/2025
Let’s break down the most common issues with Electric Power Steering (EPS) straight from real-world cases, forums, and expert articles.
👉 You're not alone. These are some of the most frequent problems mechanics and drivers face and here's what’s behind them.
1. Sensor Malfunctions & Calibration Issues
Torque sensor failure is one of the most frequent EPS faults. It may send incorrect data to the ECU, resulting in uneven or total loss of assistance. Sometimes, the rack moves slightly on its own when the engine starts.
Steering angle sensor issues are also common. If it's not calibrated properly, the power assist may be stronger in one direction than the other.
2. Wiring & Electrical Issues
Loose connections, wire damage, corroded terminals, blown fuses or relays can cause intermittent or total EPS failure.
Water ingress and poor sealing are common causes of electrical failure in racks.
3. ECU (Control Module) Failure or Software Bugs
ECU can malfunction due to impact, moisture, or internal circuit board defects. This often causes random loss of steering assist with no external damage. Software issues or faulty soldering may also be to blame. In some cases, ECU replacement or reprogramming solves the problem.
4. Electric Motor Failure
The motor can overheat or wear out over time. If this happens, steering becomes heavy and unassisted.
5. Power Supply Problems (Battery / Alternator)
A weak battery or failing alternator can affect EPS performance.
Swipe through to find out what’s going on under your hood.
⚠️ Real-World Symptoms of EPS Rack Failure
EPS warning light: Yellow "Check Steering" light or error message on the dashboard.
Heavy steering: Especially during low-speed maneuvers or parking.
Uneven assistance: Steering easier in one direction than the other.
Intermittent failure after rain: Common sign of ECU or wiring damage.
Noise, vibration, looseness: Could be mechanical rack wear, not electrical.
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