Enter the error code and car brand

Vehicle engine and/or automatic transmission

Code: P0720 - The Output Speed Sensor (OSS) circuit, which monitors how fast your transmission is spinning, has a problem or is not working correctly.

When you see a P0720 pop up, it’s your car’s way of telling you there’s a glitch with the output shaft speed sensor circuit. In my years wrenching on transmissions, I’ve seen this sensor become the unsung hero that keeps your shifting smooth, your speedometer honest, and your cruise control engaged. The PCM or TCM (basically your car’s main computer brains) keeps a close eye on this sensor. If the signal coming in is jumpy or just plain missing, that’s when you’ll see the P0720 code thrown. Some folks call this part the vehicle speed sensor, but whatever the name, its job is to report how fast the transmission’s output shaft is spinning. The computer cross-checks this speed with engine RPM and input shaft speed to make sure all the gears are dancing in sync. When the numbers don’t line up, it’s a dead giveaway something’s off-so the computer stores this code. It’s definitely a transmission-related code, and you might see it alongside others like P0715 or P0500. If you’re seeing it, don’t ignore it-your car’s trying to tell you something’s not right down there.

Causes of obd2 code P0720

From my time under the hood, the number one reason for a p0720 is a faulty output shaft speed sensor-no surprise there. But believe me, that’s just the start. When I’m chasing down this code, I always check for:

Bad output shaft speed sensor (OSS) - Nine times out of ten, this is your culprit.
Busted, frayed, or corroded wiring or connectors in the OSS circuit - Even a little corrosion can cause headaches.
Shorts to ground or power in the OSS wiring - Electrical gremlins like these can totally mess with the sensor’s signal.
Open circuits in the OSS wiring - That’s just a fancy way of saying a wire’s broken or disconnected somewhere.
PCM or TCM malfunctions - This doesn’t happen often, but I’ve seen it once or twice in my career.

Most times, you’re looking at a simple sensor or wiring issue. But I never point fingers at the computer until I’ve ruled out everything else. You’ll see this code in Fords, Infinitis, and Nissans quite a bit, so it’s not just one brand’s headache.

Symptoms of obd code P0720

When P0720 rears its head, your car won’t be shy about it. Here’s what drivers usually report, and what I look for right away:

Delayed or harsh shifting - Transmission acting up? It’s probably not just your imagination.
Speedometer weirdness - If your speedometer drops to zero or starts bouncing around, the sensor might be to blame.
Cruise control cuts out - That speed data is mission-critical for cruise, so if the info’s bad, cruise won’t play along.
Check engine light - The classic warning sign. If you see this and the other symptoms, P0720 should be on your radar.

Spot any of these? Especially shifting issues and a misbehaving speedometer? Odds are you’re dealing with this code. If you’re wrenching on a Ford F-150 and you see the ford f150 code p0720, this info absolutely applies.

Diagnosis of P0720 code

Here’s how I track down a P0720, step by step, using the same process I’ve used for years in the shop:

First thing’s first, do a visual check. Pop that hood. Look for obvious wiring damage or loose connectors at the output shaft speed sensor. Water and corrosion are sneaky-if you’ve driven through puddles or snow, take a closer look for green fuzz or rust in the connectors.
Next, test the sensor. Pull the connector, check for bent or busted pins. Got a multimeter? Check sensor resistance against factory specs (you’ll find these in the service manual). Way out of range? Time for a new sensor.
Then, check the wiring. With the sensor unplugged, use your multimeter to check continuity from the plug back to the PCM/TCM. If the circuit’s open or you find a short to ground or power, there’s your issue.
Don’t forget to scan for related codes. Seeing P0715 or P0500 too? Those extra codes can give you a better idea if it’s the sensor, the wiring, or something bigger.
If you’ve ruled out everything else, maybe-just maybe-it’s the PCM/TCM. That’s rare, but if you’re stuck, it might be time to call in a pro with advanced diagnostics.

Start with the easy stuff-wiring and connectors-before you even think about swapping parts. If you’re not comfortable with a multimeter, don’t be shy about asking for help. If you’re working on a Nissan, knowing the nissan p0720 output speed sensor location will save you a ton of time during troubleshooting.

Common mistakes with P0720 trouble code

A classic mistake I see all the time? Folks tossing in a brand-new output shaft speed sensor without checking the wiring or connectors first. That’s a quick way to waste cash and not fix a thing. Another misstep? Ignoring related codes or not scanning for them at all-sometimes there’s a bigger picture you’re missing. And don’t forget, blaming the PCM right off the bat almost never solves the problem. Stick with the basics and work methodically. If you’re driving an Infiniti or Nissan and the problem doesn’t clear up, don’t overlook nissan dtc p0720 as part of your research. Sometimes the answer is hiding in the details.

Seriousness of dtc P0720

Let’s be real-this isn’t a code you can just brush off. Keep driving with P0720 active, and you’re flirting with disaster. Transmission shifts can get unpredictable or refuse to happen, which is downright dangerous if you’re in traffic. No speedometer? Now you’re guessing your speed-not good. Cruise control won’t work either. Even worse, all that erratic shifting can chew up your transmission, leading to a repair that’ll make your wallet cry. I’ve seen cars go from a simple sensor swap to needing a full rebuild just because someone ignored this code. Don’t let it get that far-deal with it sooner rather than later.

Repair steps for P0720 engine code

Once you’ve tracked down the culprit, here’s my go-to repair process for a P0720:

Swap out the output shaft speed sensor if it’s bad or out of spec. Simple and effective.
Patch up or replace any damaged wires or connectors in the OSS circuit. Make sure every connection is solid and corrosion-free.
Clean out any moisture or corrosion in the connectors, and use a dab of dielectric grease to keep future gremlins at bay.
If you’re sure the PCM or TCM is the problem (rare, but possible), you might need a reflash or replacement. But only go there after you’ve checked everything else.

After the fix, clear that code and take her for a spin. Double-check for any new or lingering codes just to be sure you nailed it the first time.

Conclusion

Bottom line: P0720 means your car’s computer isn’t getting the right info from the output shaft speed sensor, and that throws off shifting, your speedometer, and cruise control. In my experience, a bad sensor or some crusty wiring is usually to blame, so always start with a thorough inspection. Don’t drag your feet-this is a high-priority problem that can snowball into major headaches if ignored. Work methodically: check the sensor, trace the wires, and don’t point fingers at the computer until you’ve ruled everything else out. Quick, careful action is the best way to keep you-and your transmission-happy on the road.

Video for "Error p0720" on YouTube