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U3503: Control Module Input Power A Circuit Intermittent/Erratic

System
Vehicle Systems

What Does U3503 Mean?

U3503 is a diagnostic trouble code indicating: Control Module Input Power A Circuit Intermittent/Erratic. This code relates to the vehicle systems system. The vehicle's computer detected a condition outside normal operating parameters and stored this code.

What To Do Next

  1. 1
    Find your vehicle above

    Click your make and model for real owner reports and common causes specific to your vehicle.

  2. 2
    Check for recalls

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

  3. 3
    Get a professional diagnosis

    A code alone doesn't identify the exact failed part. A diagnostic ($50–$150) pinpoints the root cause.

Related Codes

U3500 Control Module Input Power A Circuit Range/Performance U3501 Control Module Input Power A Circuit Low U3502 Control Module Input Power A Circuit High U3504 Control Module Input Power B Circuit Range/Performance U3505 Control Module Input Power B Circuit Low U3506 Control Module Input Power B Circuit High U3507 Control Module Input Power B Circuit Intermittent/Erratic U3508 Control Module Input Power C Circuit Range/Performance