OBD-II Code P0713 — What It Means & How to Fix It

What Does This Error Mean?

P0713 means the Transmission Fluid Temperature sensor circuit is reading high voltage — the TCM interprets this as an open sensor or impossibly cold fluid (below -40°F). The most common cause is a broken connector or open-circuit sensor. Default shift settings activate, often felt as firmer shifts than usual.

Affected Models

All vehicles 1996+ with automatic transmissions
Common in GM trucks with 4L60E and 6L80
Common in Ford F-150 with 6R80 and 10R80
Common in Toyota with A750 and AB60

Common Causes

Open-circuit TFT sensor (internal break in the sensor element)
Disconnected TFT sensor connector at the transmission
Wiring open between sensor and TCM
Corroded connector pins preventing electrical contact
Failed TCM input pin (rare)

How to Fix It

Pull freeze frame data.

A reading at the maximum value (e.g., -40°F) when the engine is clearly warm confirms an open circuit, not a real cold reading.
Inspect the TFT sensor connector.

On many vehicles the connector is exposed to road debris and can pop off. Reseat firmly and check for damaged pins.
Test sensor resistance.

Disconnect the sensor and measure resistance. A reading of OL (open line) confirms the sensor element is broken internally and needs replacement.
Inspect wiring for breaks.

Trace the wiring from sensor to TCM. Look for chafed or pinched sections — a broken wire causes the same symptom as a broken sensor.
Replace the sensor if confirmed open.

External sensors are easy DIY. Internal sensors (valve body integrated) require professional fluid service and removal of the transmission pan.

When to Call a Professional

If the sensor connector is found disconnected, simply reseating it can resolve P0713 for free. Replacement of an internal sensor requires pan drop and fluid service — USD 200–400 at a shop. External sensors on older GM cost USD 50 in parts and 20 minutes labour.

Frequently Asked Questions

Why did P0713 set after my last transmission service?

A common cause of P0713 right after service is the technician forgetting to reconnect the TFT sensor connector. Return to the shop — the fix is a 30-second reconnect and free. A second possibility is a damaged pin from rough handling — also covered by the shop's warranty.

Will P0713 affect fuel economy?

Yes, slightly. The TCM uses default fluid temperature assumptions when the sensor reads open, which results in less optimal torque converter lockup and shift timing. Fuel economy can drop 5–10%. Fix the sensor to restore normal operation.