Injection Pump B Control Circuit Low
Indicates a low voltage condition in the injection pump control circuit B.
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 engine control module (ECM) is not getting enough voltage or signal from the injection pump's control circuit B, which regulates how fuel is delivered.
What the computer is actually seeing
The ECM expects a specific voltage signal (approximately 5V) from the injection pump control B circuit but detects a lower value, indicating a fault.
What a healthy reading looks like
Expected voltage in the control circuit should be around 5 volts; anything below 1 volt is considered low.
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.
- 1Check the wiring and connectors for the injection pump control circuit B for damage or corrosion.
- 2Measure the voltage at the control circuit B connector with the ignition on. Expected voltage is around 5 volts. If below 1 volt, continue to next step.
- 3Inspect the ground connection for the injection pump and ensure it is solid and free of corrosion.
- 4If wiring and ground check out, test the injection pump. Measure voltages and resistances according to manufacturer specs.
- 5If the injection pump fails tests, replace it and clear the code. If everything checks out but the code persists, consider ECM issues.
Common causes
- Bad wiring or connectors in the injection pump control circuit
- Faulty injection pump
- Damaged ECM
- Poor ground connection
Typical repair cost
$$
Related codes
Frequently asked questions
Is it safe to drive with this code?
With moderate severity, it may run rough or have reduced power; drive with caution and repair soon.
Will this code come back after clearing?
It can return if the underlying issue isn't fixed. Be sure to diagnose fully.
Why does this code appear alongside others like P0251?
These codes indicate similar issues related to the fuel injection system, often pointing to circuit or sensor problems.
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