P0720 OBD-II Trouble Code: Output Speed Sensor Circuit Malfunction

Our certified mechanics come to you · Get a fair and transparent estimate upfront

EXCELLENT RATING ON

Cost of diagnosing the P0720 code

P0720 is a diagnostic trouble code (DTC) for "Output Speed Sensor Circuit Malfunction". This can happen for multiple reasons and a mechanic needs to diagnose the specific cause for this code to be triggered in your situation. Our certified mobile mechanics can come to your home or office to perform the Check Engine Light diagnostic for $154.99 . Once we are able to diagnose the problem, you will be provided with an upfront quote for the recommended fix and receive $50.0 off as a credit towards the repair. All our repairs are backed by our 12-month / 12,000-mile warranty.

Cars Estimate* Credit towards follow-up repair Earliest Availability
Ford $154.99 $50.0
Toyota $154.99 $50.0
BMW $164.99 $50.0

*Estimates may vary by market

SCHEDULE P0720 DIAGNOSTIC Get a fair and transparent estimate upfront

P0720 code definition

The P0720 trouble code notes an error with the output speed sensor circuit.

What the P0720 code means

The P0720 code is a standard OBD-II trouble code that detects an issue with the output speed sensor circuit. The powertrain control module (PCM) relies on a signal from the output speed sensor, so that it can determine the correct shift strategy and send that information to the transmission. If the PCM fails to receive information from the output speed sensor, or the information is sporadic, erratic, or simply not a slow and steady increase, the P0720 trouble code will be triggered.

What causes the P0720 code?

There are a handful of different issues that can result in the P0720 code, including:

  • Malfunctioning output speed sensor
  • Malfunctioning input speed sensor
  • Damaged or corroded wires, or loose connectors
  • Contaminated or low transmission fluid
  • Faulty engine drivability sensors
  • Malfunctioning shift solenoids
  • In very rare cases, a defective PCM

What are the symptoms of the P0720 code?

When the P0720 code is detected, the check engine soon warning light will likely illuminate. The vehicle will also may have engine and transmission issues, including an inability to shift, a harsh shift feel, an erratic or malfunctioning speedometer, hesitation and misfiring from the engine, and potentially stalling. The vehicle may also experience a decrease in fuel efficiency.

How does a mechanic diagnose the P0720 code?

The P0720 code will be diagnosed using a generic OBD-II trouble code scanner. A reputable technician will start by examining the freeze frame data from the trouble code scanner, which will give them information about the code, and will allow them to search for additional trouble codes that have been detected. The trouble codes will then be reset, and the vehicle restarted and briefly driven. If the P0720 code does not return, it likely is an intermittent issue, rather than a problem with the output speed sensor.

If the P0720 trouble code is still detected, then the technician should begin by examining any basic issues that may be triggering the code, such as the wires, connectors, and transmission fluid. When any issue is found, it should be resolved, and the codes should be reset.

If the code persists, the mechanic will test the output speed sensor’s ground signals and reference voltage. If either circuit is open, it will need to be replaced.

Common mistakes when diagnosing the P0720 code

The most frequent mistake made when diagnosing the P0720 trouble code comes from failing to follow the OBD-II trouble code diagnosis protocol. All steps should be followed in order to make sure that the inspection and repair is both thorough and efficient.

Failure to follow the trouble code diagnosis protocol can result in the output speed sensor being erroneously replaced when a much simpler issue was the problem.

How serious is the P0720 code?

In most cases the P0720 code does not keep a car from being drivable. However, the effects of the code can get worse if it is not repaired, and further damage can be caused to the transmission.

What repairs can fix the P0720 code?

Repairs for the P0720 trouble code include:

  • Replacement of the output speed sensor
  • Replacement of the input speed sensor
  • Replacement of the wires or connectors
  • Drain and refill of the transmission fluid
  • Replacement of the PCM

Additional comments for consideration regarding the P0720 code

The P0720 code is often joined by an input speed sensor code.

After the faulty components have been replaced, a technician should check to see if other engine issues caused damage to the output speed sensor or other components. For example, if the sensor failed due to an engine leak, then the leak needs to be fixed, not just the sensor.

Need help with a P0720 code?

YourMechanic offers certified mobile mechanics who will come to your home or office to diagnose and repair your vehicle. Get a quote and book an appointment online or speak to a service advisor at 1-800-701-6230.

Check Engine Light
P0720
trouble codes

No more waiting rooms! Our mechanics will come to you to diagnose and fix the P0720 code.

SCHEDULE P0720 DIAGNOSTIC
Get a $50 credit for the follow-up repair

Recent Check Engine Light is on Inspection reviews

Excellent Rating

(8600)

Rating Summary
8017
273
65
46
199
8017
273
65
46
199
 at YourMechanic

Brandon

9 years of experience
133 reviews
Brandon
9 years of experience
Ford Escort L4-2.0L - Check Engine Light is on - Nashville, Tennessee
Brandon showed up ahead of schedule, was very personable and diagnosed my problems. He also scheduled my next appointments which will be with him.
 at YourMechanic

William

23 years of experience
33 reviews
William
23 years of experience
Lexus IS250 V6-2.5L - Check Engine Light is on - Mableton, Georgia
Arrived early which was great. William was courteous, and attentive to the issue. Even though it took several attempts I'm so happy he was determined to fix it and he did!
 at YourMechanic

Dan

40 years of experience
1080 reviews
Dan
40 years of experience
Plymouth Grand Voyager - Check Engine Light is on - Lawrenceville, Georgia
Mr. Dan Barber was quite patient, courteous and quite knowledgeable. From my observation, Mr. Barber appears to be quite professional.
 at YourMechanic

Christopher

9 years of experience
120 reviews
Christopher
9 years of experience
Ford Fiesta L4-1.6L - Check Engine Light is on - Smyrna, Georgia
Chris communicated with us each step of the way up until his arrival. He listened well, was knowledgeable, and was prepared. He took the time to diagnose the problem, explained the what, why and how and provided a solution. I would definitely recommend him and will use him again.


Related questions

Diagnostic brought up three codes
Hi there. The codes that you are getting indicate a couple of different issues. The P0700 and P0720 codes indicate a transmission problem. These indicate a failure in the transmission output speed sensor. I have seen more wiring issues than...
p0720 code will not stay gone
Hello. If the vehicle speed sensor has been replaced then the wiring to the sensor must be tested. If there is high resistance or any breaks in the wire then this will occur. I have also seen the signal gear...
P0720 and P1529 codes and speedometer is not working.
Hi there. The OBD-II Error code P0720 (https://www.yourmechanic.com/article/p0720-obd-ii-trouble-code-output-speed-sensor-circuit-malfunction-by-brady-klopfer) indicates that a transmission speed sensor is faulty or receiving faulty data; which can cause your speedometer to not function. In most cases, this is more of an inconvenience, however, the speed...

More related articles

P0059 OBD-II Trouble Code: Heater Circuit Resistance (Bank 2 Sensor 1)
P0059 P0059 trouble code definition The definition of diagnostic trouble code p0059 is that the resistance for the heater circuit of bank 2 sensor 1 oxygen sensor is not correct. What the P0059 code means When this trouble code sets...
P0714 OBD-II Trouble Code: Transmission Fluid Temperature Sensor Circuit Intermittent
P0714 code means there is an abnormal transmission temperature often due too low transmission fluid and faulty parts.
P0799 OBD-II Trouble Code: Pressure Control Solenoid “C” Intermittent
P0799 means that there is an issue with one of the pressure control solenoids due to faulty wiring, low or dirty fluid, or defective solenoid.

How can we help?

Our service team is available 7 days a week, Monday - Friday from 6 AM to 5 PM PST, Saturday - Sunday 7 AM - 4 PM PST.

1 (855) 347-2779 · hi@yourmechanic.com