Fuel Pump Secondary Circuit Malfunction
This code indicates a problem in the fuel pump's secondary circuit.
Heads up: this code wasn't in our hand-written library yet, so DiagCoach AI built this page on the fly. Double-check critical specs against service info before condemning parts.
What it means (plain English)
The computer is detecting that the fuel pump isn't getting the right signal or power it needs, which can cause issues with fuel delivery to the engine.
What the computer is actually seeing
The engine control module (ECM) monitors the fuel pump circuit for voltage inputs between 0-12V. If it sees a voltage drop or no voltage when it expects to see it, it throws the P1230 code.
What a healthy reading looks like
A functioning fuel pump circuit should show around 12V when the key is in the ON position and the pump is activated.
Guided diagnostic — the DiagCoach way
Don't just throw parts at it. Walk through these in order — each step tells you whether to keep going or stop and fix what you found.
- 11. Inspect the fuel pump relay for functionality. Check for a clicking noise when activated and ensure voltage at the relay terminals.
- 22. Check the wiring and connectors leading to the fuel pump for corrosion, breaks, or overheating signs. Repair any faults found.
- 33. Test the fuel pump directly by applying battery voltage to it. If it doesn't run, replace it and retest the system.
- 44. Measure the voltage at the fuel pump connector with the key in the ON position. Expect around 12V. If not present, trace wiring back to the ECM or relay for issues.
- 55. If necessary, test the ECM with a scan tool to ensure it's sending the right signals and hasn’t logged other related fault codes.
Common causes
- Bad fuel pump relay
- Faulty fuel pump
- Corroded connectors or wiring
- ECM failure
- Fused relay opening
Typical repair cost
$$
Related codes
Frequently asked questions
Is it safe to drive with this code?
Moderate severity means you might experience performance issues, so it's best to fix it soon but it's usually safe to drive for a short time.
Will this code come back if I clear it?
If the underlying issue isn’t fixed, it will likely return after clearing.
Why might this code appear after I filled up with gas?
If the fuel system is clogged, it can drag down the fuel pump's performance and trigger this code.
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