P0720 — Output speed sensor circuit

What this code generally means, its most common causes, and how serious it is.

TYPE: GENERICSYSTEM: TRANSMISSION

What does the code P0720 mean?

The output speed sensor tells the transmission control module how fast that part of the transmission is turning — essential information for deciding when and how to shift. This code flags a problem in that specific circuit.

Common possible causes

A failing sensor — the most common cause.
Damaged wiring or connector — exposed to transmission heat and vibration.
Metal debris or shavings on the sensor — can also be a sign of internal transmission wear.

General severity

Moderate to serious — worth a prompt check

This code can cause harsh, delayed, or erratic shifting. It usually isn't an immediate breakdown risk, but is worth checking fairly soon to avoid worsening internal wear if that's the real cause.

This is still a general severity for this code, not a diagnostic for your car. Only a real read of your codes, with your mileage and vehicle history, can tell what's really going on.

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Meca doesn't replace an in-person check by a professional. For any serious sign (a flashing light, a major loss of power, a fuel smell), see a mechanic promptly.

Frequently asked questions

My shifts feel harsh — is that related?

That's a common symptom of this code — the transmission module needs a reliable speed reading to time gear changes properly.

Is metal debris a serious sign?

It can be a sign of internal transmission wear rather than just a sensor problem — worth a more thorough check.

Can I keep driving?

Usually yes short-term, but avoid long trips until checked if shifting feels clearly abnormal.