U3503
Control Module Input Power A Circuit Intermittent/Erratic
U3503 is an OBD-II diagnostic trouble code meaning: Control Module Input Power A Circuit Intermittent/Erratic. Common causes: poor contact in module connectors, broken or damaged wires in the power circuit. Estimated repair cost: $6–167.
Symptoms
- Periodic failures in the operation of electronic systems
- Spontaneous shutdown of devices
- Check Engine Light Is On
- Lost connection with diagnostic equipment
- Incorrect sensor readings
Causes
- Poor contact in module connectors
- Broken or damaged wires in the power circuit
- Faulty relay or fuse
- Alternator or battery problems
- Malfunction of the control module itself
How to Fix
- Check the condition of the battery and generator
- Inspect the power circuit for damage
- Check contacts in module connectors
- Test relays and fuses
- Diagnose the control module itself
Related codes
Error U3503 by Vehicle Brand
FAQ
What does the U3503 code mean?
U3503 is an OBD-II diagnostic trouble code that indicates: Control Module Input Power A Circuit Intermittent/Erratic
What causes a U3503 error code?
The most common causes of U3503 include: Poor contact in module connectors; Broken or damaged wires in the power circuit; Faulty relay or fuse; Alternator or battery problems.
How do I fix a U3503 diagnostic trouble code?
To fix U3503: Check the condition of the battery and generator. Inspect the power circuit for damage. Check contacts in module connectors. For a complete diagnosis, use an OBD-II scanner.
Is it safe to drive with U3503?
Limited driving only, diagnose soon
How much does it cost to fix U3503?
The estimated repair cost for U3503 is $6–167. Actual cost depends on your vehicle, location, and labor rates.
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