Common Symptoms
- Check Engine Light illuminated
- Fuel pump runs continuously even with key off
- Battery drain after vehicle is parked
- Fuel pump relay clicking repeatedly
- Engine may run normally despite code being set
Most Likely Root Causes
- Shorted fuel pump relay or relay driver circuit
- Damaged wiring harness causing short to power
- Faulty powertrain control module internal driver
- Corroded or damaged fuel pump control module
- Water intrusion in fuel pump controller connector
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Component Location
Fuel pump relay is typically in the power distribution center under the hood or in the fuse panel near the driver's side footwell.
Manufacturer Notes
Some manufacturers use a secondary fuel pump circuit for high-demand situations or dual pump systems where this circuit controls auxiliary pump operation.
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