01 Activists Using Cones to Disable Self-Driving Cars in San F… • 02 CVT Transmission Continuously Variable Gear Mechanism • 03 Feeling the Heat? Troubleshoot Your Car's AC System Problem… • 04 Understanding Engine Knocking: Causes, Signs, Prevention, T… • 05 C0000 - Vehicle Speed Information Circuit Malfunction • 06 What to Do If Your Electric Car Runs Out of Charge in the M… • 07 In-Depth Look at ABS: How Your Brakes Adapt to Prevent Whee… • 08 Mass Air Flow Sensor (MAF): How It Works, Symptoms and Prob… • 09 The Ultimate Guide to Inspect a Used Car Before Buying • 10 Extend Your Car's Lifespan to 300000 Miles with These Power… •

DTC codes / Jaguar codes / P1722

P1722 · JaguarStall Speed

P1722 on Jaguar vehicles indicates the transmission control module (TCM) has detected an implausible relationship between engine speed and expected stall speed during a stall test or while the torque converter is under load. The TCM compares signals from the crankshaft position sensor and transmission input/output speed sensors to determine if the engine stalls or slips outside the programmed stall speed window, which typically points to a torque converter or internal transmission fault.

SystemPowertrain
Code typeJaguar specific
SeverityMedium
Fix difficultyProfessional
AreaTransmission

Symptoms you may notice

  • Illuminated check engine light or transmission warning light, often with no other noticeable symptoms
  • Engine stalling or stumbling when coming to a stop or during idle in gear
  • Harsh or delayed gear engagement, especially when shifting from Park to Drive or Reverse
  • Transmission slipping or flaring during acceleration, with engine RPM rising faster than vehicle speed
  • Reduced power or limp mode activation with the transmission stuck in a single gear
  • Abnormal noise or vibration from the transmission area during idle or low-speed maneuvers

Common causes, most likely first

  1. Faulty torque converter, such as a failed stator clutch or worn lock-up clutch, causing incorrect stall speed
  2. Low or contaminated transmission fluid, leading to poor hydraulic pressure and abnormal stall characteristics
  3. Defective transmission input or output speed sensor, sending erratic signals to the TCM
  4. Internal transmission damage, including worn clutch packs or valve body issues, affecting stall speed under load
  5. Engine performance problems, such as a faulty mass airflow sensor or vacuum leak, that alter engine stall speed
  6. Wiring or connector issues between the TCM and speed sensors, causing intermittent signal loss
  7. TCM software calibration issues or internal TCM faults, though less common

How to diagnose and fix it

  1. Check transmission fluid level and condition; top off or replace fluid if low or contaminated
  2. Perform a visual inspection of the TCM and speed sensor wiring for chafing, corrosion, or loose connectors
  3. Use a scan tool to read live data from the crankshaft, input, and output speed sensors during a stall test to verify signal consistency
  4. Conduct a stall speed test following Jaguar procedures to compare actual stall speed against specifications
  5. Test the resistance and signal output of the transmission input and output speed sensors; replace if out of specification
  6. Inspect the torque converter for proper operation, including stator clutch function, and replace if faulty
  7. If all external checks pass, perform internal transmission diagnostics or rebuild/replace the transmission as needed

Stall Speed Code Isn't Always the Converter

  • A common misdiagnosis is replacing the torque converter immediately, but engine performance issues like a dirty mass airflow sensor or a vacuum leak can alter stall speed and set P1722 without any transmission fault.
  • Low transmission fluid level is frequently overlooked; even a slight leak can cause aeration and erratic stall speed readings that trigger this code.
  • The TCM may set P1722 if the crankshaft position sensor signal is intermittent, so always check engine speed sensor wiring and connectors before condemning the transmission.
  • On some Jaguar models, a weak battery or charging system fault can cause voltage drops that disrupt TCM communication and falsely set P1722.
  • After repairs, the TCM adaptive learning must be reset and a relearn drive cycle performed, otherwise the code may return even with a correct repair.

Can I keep driving with P1722?

You can drive the vehicle cautiously to a repair shop if the transmission is not slipping severely and the engine is not stalling repeatedly, but avoid heavy acceleration, towing, or prolonged driving to prevent further transmission damage. If the engine stalls frequently or the transmission enters limp mode, stop driving and arrange a tow.

Tools that help

Tools we recommend are in the Auto Veteran shop on Amazon. As an Amazon Associate we earn from qualifying purchases.

Guidance is general and written for Jaguar vehicles. Exact tests and values vary by model, so confirm the fault before replacing parts.

Running on fumes Free guides aren't free to make. Top up the tank. Any amount, one time. Fuel the Garage