P0711
PowertrainTransmission Fluid Temperature Sensor Circuit Range/Performance
Most of the time this comes down to the fluid temperature sensor itself going lazy with age, or its wiring playing up where it dives into the gearbox. The sensor lives inside the transmission and feeds a temperature reading to the gearbox control module, which uses it to decide shift timing and line pressure. When that reading drifts out of range or jumps around erratically, the module decides the signal can't be trusted and logs P0711. It shows up a fair bit on older ZF autos and the VAG DSG boxes, often alongside a limp mode complaint.
ⓘ Information only. This page provides general educational information about fault code P0711. We do not assess the urgency or safety implications of any specific fault. That requires in-person diagnosis by a qualified mechanic. Full terms.
Recommended next steps
Whether a fault is urgent, drivable, or routine depends entirely on the cause on a specific vehicle, and that can only be determined by a qualified mechanic with diagnostic equipment. If a warning light is illuminated, the most reliable next step is professional diagnosis.
What does P0711 mean?
P0711 is a Powertrain (engine, transmission, fuel system) fault code. It indicates: Transmission Fluid Temperature Sensor Circuit Range/Performance.
This is a standardised OBD-II code. The technical definition is the same regardless of the make or model of vehicle, although specific causes and symptoms can vary between vehicles.
Symptoms commonly associated with this code
Symptoms that drivers often report alongside this code. Not all may apply to every case:
- • Engine warning light on, sometimes with a separate gearbox or transmission temperature warning
- • Harsh or delayed shifts, especially noticeable from cold or under load
- • Gearbox dropping into limp mode and locking you into one gear, usually third
- • A flared or hunting feel between gears as the box second-guesses itself
- • Burnt smell off the fluid if the box has actually been overheating
- • Slightly worse economy because the gearbox is shifting at the wrong points
Possible causes
Causes commonly associated with P0711, listed in approximate order of typical investigation. The actual cause on a specific vehicle can only be confirmed by professional diagnosis.
- 1. The temperature sensor worn out or reading erratically, the usual culprit on high-mileage automatics. It's often built into the internal wiring loom rather than a standalone part
- 2. Damaged or corroded wiring at the gearbox connector, where heat and road muck attack the harness over years
- 3. Low or burnt transmission fluid throwing off the sensor reading, common on cars that have never had a fluid service
- 4. Faulty internal wiring sleeve or sensor harness inside the sump, which means dropping the pan to fix
- 5. Transmission control module fault or a software issue misreading a perfectly good sensor
- 6. The gearbox actually overheating from a mechanical fault, so the sensor is telling the truth and the box is the real problem
- 7. Corroded pins at the sensor terminal breaking up the signal intermittently
How mechanics typically diagnose
A typical diagnostic sequence used by mechanics, provided here for educational reference only. Diagnostic work should be performed by a qualified mechanic with the appropriate tools and training.
- 1. Scan the box with a tool that reads live transmission data, not just a basic code reader. Watch the fluid temperature value as the box warms up. If it reads -40C, sticks at a fixed number, or spikes wildly, you've found your fault
- 2. Check the fluid level and condition. Burnt, dark, or low fluid will skew the sensor and points to a service being overdue, so sort that before chasing electrics
- 3. Inspect the gearbox connector and harness for corrosion, oil contamination, and chafing. These connectors get baked next to the box and the pins corrode
- 4. Measure sensor resistance against temperature with a multimeter where the part is accessible. It should change smoothly as it warms. Check your specific values, but a flat or open reading confirms a dead sensor
- 5. Check continuity and for shorts between the connector and the control module, since a chafed wire mimics a bad sensor
- 6. Clear the codes, take it for a proper drive through several shift cycles, and confirm the temperature reading tracks sensibly before calling it fixed
Common questions about P0711
Should I just buy a cheap sensor off eBay or pay for a proper one? +
On the boxes where it's a standalone sensor, a decent aftermarket part from a known brand is fine and saves you a packet over dealer pricing. The catch is that on a lot of modern autos, the ZF 6HP and 8HP and the VAG DSG included, the sensor isn't sold on its own. It's part of the internal mechatronic or wiring sleeve, so you're buying the loom assembly anyway. Cheap no-name electrical bits inside a gearbox aren't worth the risk, because if it fails again you're paying the labour to drop the pan twice.
Can I keep driving like this or do I need to stop? +
Short trips to get it looked at are usually fine, but don't ignore it. If the reading is wrong the box can shift at the wrong points and run hotter than it should, and sustained heat is what kills automatic transmissions. If it's dropped into limp mode you'll be stuck in one gear with no real acceleration, which is dangerous pulling onto a motorway. Get it diagnosed within a few days rather than living with it for weeks.
Is this going to fail the MOT? +
The code on its own isn't an MOT failure. What catches people out is the warning light. If the engine management or gearbox warning light is lit when the tester looks at the dash, that's a fail under the current rules, regardless of why it's on. Fix the fault, clear it, drive a few cycles to make sure it stays off, then book the test.
What am I looking at to put it right? +
If it's a simple standalone sensor and easy to reach, an independent garage might do it for £120 to £250 all in. Where the sensor is buried in the internal loom, you're paying for the pan to come off, the part, fresh fluid and a gasket, which pushes it to roughly £350 to £600 at an independent. Main dealers will charge noticeably more, often £500 plus, and they'll usually quote the full loom rather than a single sensor. Get the fluid done at the same time, it makes sense while the pan's off.
Information only, not professional advice
The information on this page is provided for general guidance and educational purposes only. It is not a substitute for diagnosis or repair advice from a qualified mechanic. Always verify any fault before paying for repairs. carfaultcodes.co.uk accepts no liability for decisions made based on this information. Full terms →