EGR Valve Position Sensor Circuit Low - General Fault
This code indicates a low voltage condition in the EGR valve position sensor 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 EGR valve position sensor tells the computer where the EGR valve is. If it's sending low voltage signals (usually less than 0.5 volts) when it should be at a higher position, the computer flags it as a problem.
What the computer is actually seeing
The Engine Control Module (ECM) expects the EGR valve position sensor to send a voltage signal ranging from 0.5 to 4.5 volts. If it sees less than 0.5 volts, it triggers the code SPN 6720.
What a healthy reading looks like
EGR valve position should be around 0.5 to 4.5 volts depending on valve position; expect around 2.5 volts at partial lift.
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. Check the EGR valve position sensor connector for damage, corrosion, or loose connections. If found, repair or replace the connector. Decision Point: Is the connector okay? Yes - go to step 2. No - fix the connector and retest.
- 22. Measure the voltage at the EGR valve position sensor while the key is on but the engine is off. It should be between 0.5 to 4.5 volts. Decision Point: Is the voltage within this range? Yes - go to step 3. No - suspect faulty sensor or wiring.
- 33. With the engine running, monitor the EGR valve position while applying throttle. The voltage should increase correspondingly. Decision Point: Is the voltage varying as expected? Yes - check for other related codes. No - replace EGR valve position sensor.
Common causes
- Faulty EGR valve position sensor
- Wiring issues (frayed, shorted, or corroded)
- Faulty EGR valve
- Poor ground connections on the sensor
- Open circuit in the EGR sensor circuit
Typical repair cost
$$$
Related codes
Frequently asked questions
Is it safe to drive with this code?
It's not ideal; you may notice reduced power or increased emissions. It's best to fix it soon.
Can this code come back after clearing it?
Yes, if the underlying issue isn't fixed, it will likely return.
Why is this code showing up with others about the EGR system?
They often indicate multiple failures in the EGR system, which can happen if the initial issue isn't addressed.
Working a real vehicle right now?
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