What it means
Supply voltage to fuel pressure regulator A solenoid above expected range — typically charging system overvoltage. Wiring faults of this kind typically come from chafing, water ingress at connector seals, or pin push-back — a wiggle test on the harness while the code is active often confirms the location.
At a glance
- Usually lights the check-engine light
- Affects emissions; the car can fail an emissions test
- The engine or gearbox may go into limp mode
How it works
Fuel pressure regulator A's solenoid receives power through a monitored supply circuit. P00CA sets when the control module detects voltage above the expected range on that circuit, which can point to an overvoltage condition or a wiring fault that exposes the feed to a higher-voltage source.
Common causes
Most likely first.
- Alternator regulator failed
- Connector pins corroded - high contact resistance
- Supply wire pinched against B+ source
Symptoms
- Check engine light on
- Hard start, no start, or stalling under load
- Power loss especially at high load or rpm
- Possible long cranking time
How to diagnose it
- Record freeze-frame data and compare regulator A supply voltage with other system-voltage readings to see whether the fault coincided with charging-system overvoltage.
- Inspect the regulator A connector and harness for water ingress, corrosion, pushed-back pins, pinching or contact with a battery-positive feed.
- Check charging-system voltage under the conditions specified by the manufacturer and compare it with the manufacturer's specification.
- Measure voltage at the regulator A supply circuit and inspect for shorts to a higher-voltage source.
- Test the regulator A circuit, connector and charging-system regulator using the manufacturer's procedures.
Common fixes
- Repair a pinched regulator A supply wire or a short to a higher-voltage source.
- Dry, clean or replace a water-damaged or corroded connector and restore its seal.
- Repair loose or pushed-back terminals at the regulator A connector.
- Repair the charging system if testing confirms it is producing excessive voltage.
- Replace a regulator A solenoid only if testing confirms it was damaged or is faulty.
Can I keep driving?
Avoid driving if the engine stalls, runs poorly or the charging system is overcharging, since electrical faults can affect other vehicle systems. Have the supply voltage checked promptly; continued overvoltage can damage electrical components.
A code shows where the control module detected a fault, not always which part failed. Check the causes in order and confirm with a test before replacing parts. Have several codes? Check them together
This is a generic code: it means the same on every make. The car’s maker may add more detail in its own service information.