U3503

Control Module Input Power A Circuit Intermittent/Erratic

Severity

⚠️ Medium

Can you drive?

Limited driving only, diagnose soon

Approx. repair cost

$6–167 (est.)

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

U3500 U3501 U3502