P0713 Code Fix: Trans Fluid Temp Sensor High (Test First)

What Does P0713 Mean?

The Transmission Control Module needs to know how hot the automatic transmission fluid is, because fluid temperature drives line pressure, shift timing, and torque converter clutch behavior. It reads that temperature from the transmission fluid temperature sensor, a thermistor sitting in the fluid. On the common negative temperature coefficient design, the sensor's resistance is high when the fluid is cold and falls as it warms, and the TCM converts the resulting signal voltage into a temperature. P0713 is the code for that sensor circuit when the TCM sees the signal voltage too high for the range it expects.

"High Input" describes the electrical state of the circuit, not the actual heat of the fluid. When a negative-coefficient circuit opens, resistance and the measured voltage climb, so the TCM reads a value at or beyond the high end of the scale. The short list of reasons: an open sensor element, a connector that is not making clean contact, a broken or chafed signal wire, an open sensor ground, or a TCM input fault. P0713 belongs to a family of TFT Sensor A codes. P0712 is the matching Low Input code, P0711 is Range or Performance, P0714 is Intermittent, and P0710 is the generic circuit malfunction.

Here is the part that saves money. A sensor circuit has three pieces: the sensor, the wiring, and the connector that joins them. The word "transmission" in the code name pushes people toward the gearbox, but the sensor and its wiring fail far more often than the transmission does. A failed thermistor or a chafed signal wire produces the same P0713 a real fault would. The job is to find which of the three pieces is open, and that test costs nothing.

What Are the Symptoms of P0713?

Symptoms come from the TCM losing a trustworthy temperature reading and falling back to a safe strategy. A full open circuit usually triggers a protective mode; an intermittent connector comes and goes:

Is P0713 Serious?

Moderate. The transmission is usually fine, but you lose temperature protection, so handle it within about a week.

The urgency here is about losing a safety net, not about the transmission failing on the spot. With the temperature sensor open, the TCM cannot see a genuine overheating event, so do not tow or run long highway stints until it is fixed. The bigger financial risk runs the other way: paying for valve body or rebuild work on a code that is really a cheap sensor or harness. Handle the code quickly, but spend the free ten minutes confirming whether the fault is the sensor, the connector, or the wiring before approving any internal transmission work.

What Causes a P0713 Code?

The list below runs from most common to rarest. The sensor and its wiring sit at the top, and internal transmission damage is further down than the code name suggests.

What You'll Need

How Do You Fix a P0713 Code?

Work the steps in order. Step 2, the resistance-versus-temperature test, separates a bad sensor from bad wiring in a few minutes and is the one most people skip.

• 1

  Scan All Codes and Read the TFT Live Value

  Record every code and read the live transmission fluid temperature. P0713 often travels with P0712 (TFT Sensor A Low Input), P0711 (Range or Performance), P0714 (Intermittent), P0710 (generic circuit malfunction), and P0700, the generic flag that a transmission fault exists. The live temperature is the giveaway. The TFT sensor is a negative-coefficient thermistor, so an open circuit reads as a pinned value. A temperature stuck at roughly minus 40 degrees, or pinned at an impossible high reading on a cold engine, points at an open circuit, not a hot transmission. Clear the codes and restart: if P0713 returns at once, a hard fault exists, so go to Step 2; if it stays gone, clean and re-seat the connector as cheap insurance against an intermittent.

  A live TFT value that does not match a cold engine after an overnight sit is the fastest sign that the circuit, not the transmission, is the problem.
• 2

  TFT Sensor Resistance vs Temperature Test

  This is the test that decides sensor versus wiring. Unplug the transmission connector and measure resistance across the TFT sensor pins, then compare against the fluid temperature. A typical thermistor reads several thousand ohms cold near room temperature and drops to a few hundred ohms hot, so resistance falls as the fluid warms; confirm the exact resistance-versus-temperature figures in the service manual. A reading of OL or infinite means the sensor or its internal connection is open, which is the textbook P0713 cause, so replace the sensor. A reading that tracks the chart for the current temperature means the sensor is healthy and the fault is in the connector, wiring, or TCM, so leave it alone and go to Step 3. Write the reading down. An in-spec number is what keeps you from paying for a valve body or rebuild you do not need.

• 3

  Inspect the Connector and Pins

  A failing connector causes P0713 more often than internal transmission damage. Check the transmission case connector and the internal harness plug for burnt-fluid residue, green or white corrosion, melted plastic, spread pins, and a cracked locking tab. Probe each terminal for tension, since loose or splayed pins drop contact once the fluid heats up. Reconnect and run a wiggle test with live data on screen, moving the connector and harness while you watch the TFT value jump. Clean the terminals with contact cleaner, re-tension the pins or fit a new pigtail, add dielectric grease, and seat the connector until it clicks.

  Heat and fluid make the transmission connector a common P0713 culprit. A clean-up here often costs nothing in parts and resolves a real share of cases.
• 4

  Test the Signal Wire and Ground

  With the sensor and connector cleared, test the circuit to the TCM. A TFT sensor has a signal wire and a sensor ground. With the key on and the sensor unplugged, the TCM pulls the signal wire to a reference voltage, and the open state that produces is exactly the High Input fault P0713 describes. Back-probe the signal wire at the TCM connector, then check continuity from the sensor pin to the TCM pin with the key off; an open or high-resistance wire reads as the open circuit that triggers P0713. Confirm the sensor ground reads under half an ohm to a known good ground. Look for a chafe or break where the harness exits the case or crosses the bellhousing, and repair any open or chafed wire with solder and heat-shrink.

• 5

  Substitute or Bench-Check the Sensor

  Run this cross-check before opening the transmission for major work. If the TFT sensor is external or part of a serviceable pack, bench-check it by warming it with warm water or a heat gun while you watch the resistance fall on the meter. A healthy thermistor changes smoothly with temperature; a sensor that reads open or stays fixed has failed. Where the sensor is built into the internal harness or the transmission range switch, confirm the part number and that the temperature element is what failed, not just the range function. The substitution takes the guesswork out of the decision to drop the pan.

• 6

  Internal Harness, Valve Body, or TCM, Last Resort

  If Steps 2 through 5 clear the sensor, connector, and external wiring, the fault is deeper: an open in the internal transmission harness, a damaged case connector, or, rarely, a TCM input fault. This is the rarest and costliest outcome. Before authorizing any teardown, document an open or in-spec sensor reading, a clean connector with good pin tension, and continuity results on the signal and ground wires. Many transmissions put the TFT sensor on an internal harness or solenoid pack replaced with the pan dropped, far cheaper than a rebuild. A TCM that reads the signal wrong even with a good sensor and wiring may need reprogramming to the VIN.

How Much Does P0713 Cost to Fix?

The cost swings from nothing, for a cleaned connector, to a few hundred dollars for an internal harness with the pan dropped. The free resistance and continuity tests decide which end you land on before any parts are bought, and they are what keep a sensor code from turning into a rebuild quote.

A vehicle with an active P0713 fails OBD-II emissions inspection in most states until the code clears. Per the EPA Vehicle Emissions I/M Program, powertrain and emissions parts are covered under the federal emissions warranty for the first 8 years or 80,000 miles on many vehicles, so verify coverage with your dealer by VIN before paying out of pocket on a newer car.

Which Vehicles Are Most Prone to P0713?

P0713 can show up on any vehicle with an automatic transmission and a TFT sensor. GM 6L and 8L and 10L automatics, Ford 6R and 10R units, and European automatics from Audi, BMW, and Mercedes are where it surfaces most. Platform notes follow the table.

P0713 on GM 6L80, 8L90, and 10L80 Automatics

On the Silverado, Sierra, and Tahoe, the TFT sensor sits on the internal wiring harness or the transmission pressure-switch assembly, so an open often traces to the sensor or that internal harness rather than the gearbox itself. The external case connector and harness age with heat, which shows up as an intermittent that comes and goes when hot. Confirm the open with the Step 2 resistance test before deciding whether the fix is a sensor, the internal harness, or just a connector clean-up. Dropping the pan to replace an internal sensor or harness is routine and far cheaper than a rebuild.

P0713 on Ford 6R80 and 10R80

On F-150, Mustang, and Explorer automatics, the TFT sensor is part of the main control or solenoid body, and the fault is usually the sensor, the internal harness, or the case connector rather than the transmission. Tight routing and heat make the external connector a chafe and corrosion point. Because the sensor is internal on these units, the Step 2 resistance reading and the Step 4 continuity check are what decide whether you drop the pan or just clean a connector, which saves the most here.

P0713 on Audi, BMW, and Mercedes Mechatronic Units

European automatics from Audi S tronic, the ZF 8-speed in BMW and RAM, and the Mercedes 9G-TRONIC integrate the temperature sensor into the mechatronic or valve-body assembly, and water intrusion at the case connector plug is a frequent cause. Dealer rates make an unnecessary mechatronic or transmission job costly, so the free resistance and continuity tests pay off the most on these cars. A failed plug seal or a corroded case connector can set P0713 without any internal damage at all.

Should You DIY or Call a Mechanic?

Related Codes You May See With P0713

Frequently Asked Questions