01 Can You Change Your Bike's Disc Brake into a Drum Brake? • 02 The World's Biggest and Strongest Ship Engines: A Comprehen… • 03 The Real Reason Resting Your Foot On The Brake Pedal Can Wr… • 04 Can Motor Oil Substitute Transmission Fluid? A Comprehensiv… • 05 Most Owners Don’t Realize Their Car’s Interior Lights Can D… • 06 Why Does Your Car Lose Power While Driving and Now Won’t St… • 07 How the Wrong Oil Viscosity Can Mess With Your Engine's Hea… • 08 What Causes a Starter Motor to Turn Slowly and Fail to Star… • 09 If You Can't Afford Repairs, You Can't Afford the Car • 10 What Do Pilots Say When Crashing? The Truth Behind the Words •

DTC codes / P07xx · Transmission / P079E

P079ETransmission Friction Element E Slip Detected

P079E indicates that the transmission control module has detected excessive slip in friction element E, which is a clutch or band inside the automatic transmission that should hold firmly when engaged. The computer compares input and output shaft speeds and flags this code when the expected gear ratio is not achieved, meaning the element is not gripping as designed.

SystemPowertrain
Code typeGeneric (all makes)
SeverityHigh
Fix difficultyProfessional
AreaTransmission

Symptoms you may notice

  • Illumination of the check engine light or transmission warning light, often with no other noticeable symptoms
  • Harsh or delayed shifts, especially when the affected gear is engaged
  • Slipping sensation during acceleration, where engine speed rises without corresponding vehicle speed
  • Transmission may enter limp mode, limiting gear selection to a single gear or neutral
  • Shuddering or vibration during gear changes
  • Poor fuel economy or elevated transmission fluid temperature

Common causes, most likely first

  1. Worn or burnt friction plates on clutch/band E due to normal wear or overheating
  2. Low transmission fluid level caused by a leak, leading to insufficient hydraulic pressure
  3. Deteriorated transmission fluid that no longer provides the correct friction characteristics
  4. Faulty solenoid or valve body issue that prevents proper hydraulic pressure to element E
  5. Internal seal failure causing pressure loss to the clutch/band E circuit
  6. Mechanical damage to the clutch/band E assembly, such as a broken return spring or piston
  7. Transmission control module (TCM) software calibration issue or faulty pressure sensor

How to diagnose and fix it

  1. Check transmission fluid level and condition; top off or replace fluid if low or degraded
  2. Perform a visual inspection for fluid leaks around the transmission pan, cooler lines, and seals
  3. Use a scan tool to read transmission control module codes and monitor live data for slip and pressure values
  4. Test the solenoid and valve body operation for element E circuit using a bidirectional scan tool
  5. Inspect the transmission pan for debris or clutch material, which indicates internal wear
  6. Perform a pressure test on the element E hydraulic circuit to confirm pressure loss
  7. If internal damage is confirmed, remove and disassemble the transmission to replace worn clutch/band E components

Before you replace the transmission

  • A low fluid level or a clogged transmission filter can cause slip codes without any internal damage, so always verify fluid condition and level first.
  • The code may be set by a faulty pressure sensor or solenoid rather than a worn clutch, so live data and circuit tests are essential before condemning the transmission.
  • In some vehicles, a software update for the transmission control module can correct false slip detection, so check for technical service bulletins.
  • Element E may only be used in certain gears, so slip might only occur under specific driving conditions, making a road test with a scan tool essential.
  • Debris in the valve body can cause intermittent pressure loss to element E, and a simple valve body cleaning or replacement may resolve the issue without a full rebuild.

Can I keep driving with P079E?

Driving with P079E is not recommended because continued slipping can overheat and destroy the transmission, leading to a much more expensive repair. If you must drive, avoid heavy acceleration and stop as soon as it is safe to do so.

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 all OBD-II 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