Faulty engine/transmission input speed (input/turbine) sensor (both sources); OBD-Codes.com also lists the output speed sensor. Open or shorted wiring or bad connectors in the sensor circuit (both sources). Damaged or worn reluctor ring, or heavy metal deposits on the sensor's magnetic tip (OBD-Codes.com). Mechanical transmission failure causing slippage (OBD-Codes.com); RepairPal's technician notes say a speed difference between input and output often implies slipping. Faulty shift solenoids, valve body, engine coolant temperature sensor, or dirty fluid restricting hydraulic passages (RepairPal). On many vehicles a faulty crankshaft position sensor, since RepairPal says most vehicles use it for this signal.

Repair damaged wiring or clean and repair corroded connectors (both sources list wiring). Replace a faulty input/turbine speed sensor (both sources); on vehicles that use it, the crankshaft position sensor (RepairPal). Clean metal deposits off the sensor tip or repair a damaged reluctor ring (OBD-Codes.com). Service dirty transmission fluid, or repair shift solenoids or the valve body (RepairPal). Repair or overhaul the transmission if it is slipping or has failed mechanically (OBD-Codes.com).

P0725🔧 Transmission / Speed sensingStop and fix promptly

P0725: Engine Speed Input Circuit Malfunction (Meaning, Causes, Fixes)

Q: What does P0725 mean?

P0725 means the engine or transmission computer isn't getting a reliable engine speed input signal. That signal tells the transmission how fast the engine (or the transmission's input shaft) is turning so it can pick and time gears. Both sources list a faulty input speed sensor and its wiring; they differ on which sensor supplies the signal and on how much weight to give transmission slippage and hydraulic causes. OBD-Codes.com says P0725 is stored when the powertrain control module (PCM) detects a circuit malfunction with the engine speed input signal, and that this sensor is sometimes called the transmission input speed sensor. It describes a sensor fitted through the transmission case near the front of the input shaft, reading a toothed reluctor ring on that shaft. Unacceptable signals can include too much voltage, too little voltage, or a reading that doesn't make sense compared with output speed, throttle position or engine RPM, and the PCM or transmission control module (TCM) may enter limp-in mode. RepairPal says the PCM isn't seeing a reliable or rational speed signal from the transmission's input/turbine sensor, but also says the input speed signal tells the TCM how fast the engine is spinning and that most vehicles use the crankshaft position sensor for this information. That is a disagreement worth knowing: depending on the vehicle, the signal may come from a dedicated input/turbine speed sensor in the transmission or from the crankshaft position sensor, so check your vehicle's service information before buying a part. RepairPal's technician notes add that the code can set when input and output shaft speeds differ by more than a set amount, which often means the transmission is slipping. It is a generic OBD-II code (OBD-Codes.com lists Nissan, Dodge, VW, Jeep, Mazda, Honda, Chrysler and Subaru among others), but repair steps vary by make and model. Related codes are P0726 (range/performance), P0727 (no signal) and P0728 (intermittent).

Q: Can I keep driving with P0725?

Stop and fix promptly. Get it diagnosed soon and drive gently until you do. OBD-Codes.com says P0725 should be considered severe because whatever caused it may damage the transmission, and RepairPal rates it Urgent, meaning it can cause severe damage or be unsafe. If the transmission shifts harshly, slips, won't shift or drops into limp mode, avoid highway driving and have it checked.

Reviewed 2026-10-25 · Based on 2 cited source(s)

What P0725 means

OBD-Codes.com says P0725 is stored when the powertrain control module (PCM) detects a circuit malfunction with the engine speed input signal, and that this sensor is sometimes called the transmission input speed sensor. It describes a sensor fitted through the transmission case near the front of the input shaft, reading a toothed reluctor ring on that shaft. Unacceptable signals can include too much voltage, too little voltage, or a reading that doesn't make sense compared with output speed, throttle position or engine RPM, and the PCM or transmission control module (TCM) may enter limp-in mode. RepairPal says the PCM isn't seeing a reliable or rational speed signal from the transmission's input/turbine sensor, but also says the input speed signal tells the TCM how fast the engine is spinning and that most vehicles use the crankshaft position sensor for this information. That is a disagreement worth knowing: depending on the vehicle, the signal may come from a dedicated input/turbine speed sensor in the transmission or from the crankshaft position sensor, so check your vehicle's service information before buying a part. RepairPal's technician notes add that the code can set when input and output shaft speeds differ by more than a set amount, which often means the transmission is slipping. It is a generic OBD-II code (OBD-Codes.com lists Nissan, Dodge, VW, Jeep, Mazda, Honda, Chrysler and Subaru among others), but repair steps vary by make and model. Related codes are P0726 (range/performance), P0727 (no signal) and P0728 (intermittent).

Severity: can I keep driving?

Stop and fix promptly

Get it diagnosed soon and drive gently until you do. OBD-Codes.com says P0725 should be considered severe because whatever caused it may damage the transmission, and RepairPal rates it Urgent, meaning it can cause severe damage or be unsafe. If the transmission shifts harshly, slips, won't shift or drops into limp mode, avoid highway driving and have it checked.

Common symptoms

Check engine light on (both sources)
Transmission fails to shift, shifts erratically or shifts harshly in limp-in mode (OBD-Codes.com); vehicle will not shift properly (RepairPal)
Transmission slipping or delayed engagement (OBD-Codes.com); uneven shifting or slipping between gears in some cases (RepairPal)
Erratic or dead speedometer/odometer, or an incorrect or dead tachometer (OBD-Codes.com)
Lower fuel economy (RepairPal)
Other transmission input/output speed codes stored as well (OBD-Codes.com)
In unusual cases, no noticeable symptoms (RepairPal)

Likely causes

Roughly most to least common, based on the sources below. Your vehicle may differ.

Faulty engine/transmission input speed (input/turbine) sensor (both sources); OBD-Codes.com also lists the output speed sensor
Open or shorted wiring or bad connectors in the sensor circuit (both sources)
Damaged or worn reluctor ring, or heavy metal deposits on the sensor's magnetic tip (OBD-Codes.com)
Mechanical transmission failure causing slippage (OBD-Codes.com); RepairPal's technician notes say a speed difference between input and output often implies slipping
Faulty shift solenoids, valve body, engine coolant temperature sensor, or dirty fluid restricting hydraulic passages (RepairPal)
On many vehicles a faulty crankshaft position sensor, since RepairPal says most vehicles use it for this signal

Diagnostic steps you can do

⚠ Before you start

Work on a cool engine, parked on level ground with the parking brake set. Never work under a car supported only by a jack.

Check the transmission fluid level and condition first. OBD-Codes.com says fluid that smells burnt, looks very black or has a heavy metallic look points to mechanical failure, and that a level more than a quart low means checking the transmission, lines and cooler for leaks.
Inspect the sensor wiring and connectors for damage, corrosion or signs of overheating (OBD-Codes.com).
Read and write down all stored codes and freeze frame data, clear the codes and test drive (OBD-Codes.com). RepairPal says to note engine load, throttle position, RPM and road speed, because P0725 can be hard to reproduce.
If it comes back, watch the engine input speed on a scanner while driving. OBD-Codes.com says input speed that differs greatly from engine RPM points to a bad sensor or a damaged or worn reluctor ring.
If you remove the sensor, put a container underneath because hot transmission fluid may pour out (OBD-Codes.com), and check its magnetic tip for metal deposits.

Typical fixes

Repair damaged wiring or clean and repair corroded connectors (both sources list wiring)
Replace a faulty input/turbine speed sensor (both sources); on vehicles that use it, the crankshaft position sensor (RepairPal)
Clean metal deposits off the sensor tip or repair a damaged reluctor ring (OBD-Codes.com)
Service dirty transmission fluid, or repair shift solenoids or the valve body (RepairPal)
Repair or overhaul the transmission if it is slipping or has failed mechanically (OBD-Codes.com)

Repair costs vary widely by vehicle, region, parts brand and shop, so we don't quote prices. Get a written estimate after diagnosis.

🛠 When to call a pro

The transmission slips, won't shift or goes into limp mode
The fluid is burnt, black or metallic, or there's a large leak from the torque converter area, which OBD-Codes.com says suggests serious transmission failure
Testing the sensor needs a digital volt/ohmmeter, the factory specifications and sometimes an oscilloscope (OBD-Codes.com)
RepairPal warns it is commonly misdiagnosed as an engine misfire, an internal transmission problem or a driveline problem

Where to buy

Plain search links. Always match parts to your exact year, make, model and engine.

OBD2 scanners on Amazon Parts at Advance Auto Parts catalog at RockAuto

FAQs

Is P0725 serious?

Yes. OBD-Codes.com calls it severe because the cause may damage the transmission, and RepairPal rates it Urgent. It can make the transmission shift badly, slip or go into limp mode.

Which sensor causes P0725?

It depends on the vehicle. OBD-Codes.com describes a transmission input speed sensor near the front of the input shaft, while RepairPal says most vehicles use the crankshaft position sensor for engine speed input. Check your vehicle's service information before buying a sensor.

Can P0725 affect my speedometer or tachometer?

Yes. OBD-Codes.com lists an erratic or dead speedometer/odometer and an incorrect or dead tachometer as possible symptoms.

How much does it cost to fix P0725?

Neither source gives a repair cost. It ranges from a wiring repair or sensor to transmission work if it's slipping, so get a diagnosis or a written estimate before replacing parts.

Sources

Last reviewed 2026-10-25. Code definitions and repair steps can vary by manufacturer. Confirm with your vehicle's service information.