Sirion Steering Failure Due to Voltage Sensitivity

This is the most common cause, confirmed by measuring battery voltage during engine cranking. Use a multimeter to observe the voltage drop; if the reading dips into the 9–10V range, the EPS control module will fail its self-check and disable steering assist to protect the electronics. Verify this by ensuring all battery terminals and body ground straps are clean, tight, and free of corrosion, and ensure the battery holds a stable charge under load.

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