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U0100 on TOYOTA PRIUS

Severity
Medium
NHTSA Reports
2
Most Affected
2008

What U0100 Means on Your TOYOTA PRIUS

Real TOYOTA PRIUS Owner Reports (Source: NHTSA Complaints Database)

"Smog check failed because of obd bulb check failure and obdii failure. service fault codes are u0100 lost communication with ecm/pcm "a" and u0111 lost communication with battery energy control module "a." car only has 60,000 miles."

— 2008 TOYOTA PRIUS owner • ELECTRICAL SYSTEM • Filed 03/21/2017

"Driving on sb hwy 35 at 74mph, master warning light came on and vehicle shut down, no electrical or engine control. pulled safely to shoulder of road. car would not restart. got out of car, locked car, unlocked car (toyota technician instructions), then car restarted."

— 2008 TOYOTA PRIUS owner • ELECTRICAL SYSTEM,ENGINE • Filed 10/14/2014

Data from NHTSA Vehicle Complaints Database. All reports are filed by vehicle owners directly with the U.S. Department of Transportation.

Common Causes of U0100 on TOYOTA PRIUS

50%
50%

Percentages based on NHTSA complaint component analysis for this vehicle.

Complaint Trend by Year

2008
2

What To Do Next

  1. 1
    Check for recalls on YOUR VIN

    Go to nhtsa.gov/recalls and enter your VIN. Free repairs if your vehicle is covered.

  2. 2
    Get a proper diagnosis

    A code alone doesn't tell you the exact failed part. A diagnostic at a shop ($50-$150) pinpoints the root cause before you spend money on parts.

  3. 3
    Compare repair quotes

    Get 2-3 quotes. Dealer vs independent shop prices often differ 30-50% for the same repair.

U0100 on Other Vehicles

Data sourced from the National Highway Traffic Safety Administration (U.S. Department of Transportation) and the SAE J2012 OBD-II standard. Code definitions follow the SAE J2012 / ISO 15031-6 standard. Owner reports are filed directly with NHTSA by vehicle owners. This information is provided for educational purposes only and should not replace professional automotive diagnosis. Always consult a qualified mechanic for vehicle repair decisions.

Last updated: March 2026