2015 Corvette P023F — Fuel Pump Diagnostic and Replacement

The Vehicle

A 2015 Chevrolet Corvette came in on a tow truck. No start. The scan tool pulled a P023F — fuel pump control module circuit code. The vehicle had no fuel pressure and would crank but not fire.

Before pulling tools, the first step is always the same: test the circuit. A code that says "fuel pump control module circuit" does not tell you whether the problem is the module, the wiring, or the pump itself. You have to narrow it down before you start taking things apart.

Circuit Test Before Dropping the Tank

The C7 Corvette does not give you easy access to the fuel pump from inside the car. But you can get to the fuel pump connector by removing the rear wheel liner on the driver side. That gives you access to the connector and test points without committing to a full tank drop.

With the wheel liner out of the way, I placed a test light between the power and ground terminals at the fuel pump connector. Using the scan tool, I commanded the fuel pump on. The test light lit up.

That one test told me everything I needed to know. The circuit from the PCM through the fuel pump control module to the connector was intact. Power and ground were both present and the module was commanding correctly. The problem was past the connector — the pump assembly itself.

This is the step that separates diagnostic methodology from parts-swapping. One test, two minutes, and you know whether you are dealing with a wiring problem or a component failure. Without that test, you are guessing — and on a Corvette fuel pump job, guessing gets expensive fast.

Access and Disconnect

With the circuit confirmed, it was time to get the tank out. Here is where this job gets interesting.

The book calls for transmission removal on a C7 fuel pump job — the exhaust crossover pipe runs between the tank and the trans, and GM's procedure has you pull it for clearance. After years of doing this work, you learn tricks. I disconnected the crossover pipe with everything else still in place, transmission stayed in the car. Take this one connection at a time so nothing shifts or drops unexpectedly. Once the crossover pipe is out of the way, you have the clearance to drop the tank.

From there:

• Fuel fill pipe disconnected — this has to come off before the tank will drop free.
• Electrical connectors released — the fuel pump connector you already tested, plus the fuel level sender and any EVAP connections.
• Fuel lines disconnected — quick-connect fittings. Have a rag ready. Even with low pressure, there will be residual fuel in the lines.

Tank Drop

With all connections free, I supported the tank from below and removed the mounting hardware. The tank comes down cleanly once everything is disconnected. On the C7, the tank is not excessively heavy, but you still want a transmission jack or a helper — do not try to catch it solo.

Once the tank was on the ground, the pump assembly came out. The old unit was dead. No resistance reading across the pump motor terminals confirmed it — open circuit inside the pump.

Pump Replacement

New pump assembly went in, tank went back up, all connections reattached in reverse order. Crossover pipe reconnected last. Key on — the pump primed immediately. Started the car, verified fuel pressure with the scan tool, cleared the P023F code, and took it for a test drive. No codes returned. Job done.

Why Circuit Testing Matters

This job could have gone sideways fast without that initial circuit test. A P023F code on a Corvette could mean a failed fuel pump control module, a wiring issue between the module and the pump, or a dead pump assembly. If you skip the test and guess wrong, you are dropping the tank twice — or three times.

The APEX Tech Nation Academy covers fuel system diagnostics and circuit testing methodology in detail. The principle is always the same: test before you replace. Confirm before you commit. The two minutes you spend with a test light save you hours on the other end.

If you want AI-assisted diagnostics that walk you through this kind of systematic approach on any vehicle, APEX Tech Pro gives you a master-tech-trained diagnostic engine in your pocket. Describe the concern, get a structured plan — built by techs, for techs.