Fuel Pump Control Circuit - Open
The fuel pump control circuit has an open condition.
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 trying to tell the fuel pump to run but isn't getting any response, which usually means a break in the wiring or a faulty pump.
What the computer is actually seeing
The engine control module (ECM) expects to see a voltage signal (typically around 12V) from the fuel pump relay to turn on the fuel pump but detects no voltage due to the open circuit.
What a healthy reading looks like
When the fuel pump is commanded on, voltage should be between 10-14V at the pump connection. An open circuit will show 0V.
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.
- 1Inspect the wiring and connectors for any visible damage or corrosion. Decision Point: If damage is found, repair it; if not, go to step 2.
- 2Check the fuel pump relay operation. Remove the relay and check for continuity. Decision Point: If the relay is faulty, replace it; if it checks out, go to step 3.
- 3Using a multimeter, measure voltage at the fuel pump connector while cranking the engine. Decision Point: If you see power, the pump is likely at fault; if no power, go to step 4.
- 4Check the fuse related to the fuel pump circuit. Decision Point: If the fuse is blown, replace it; if it’s good, proceed to testing the ECM input/output signals.
Common causes
- Broken or damaged wiring in the fuel pump circuit
- Faulty fuel pump relay
- Defective fuel pump
- Corroded connectors
- Improper installation or disconnection of electrical components
Typical repair cost
$$$
Related codes
Frequently asked questions
Is it safe to drive my truck with this code?
No, it may cause a no-start condition or stalling while driving, so fix it as soon as possible.
Will this code come back after I fix it?
If you properly resolve the open circuit, it should not return unless there’s an intermittent fault.
Why does this code sometimes pair with SPN 6368?
SPN 6368 indicates fuel pump circuit shorted to ground; both codes highlight issues in the same circuit.
Working a real vehicle right now?
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