P079D OBD II Trouble Code Transmission Friction Element D Slip Detected

How to quicky diagnose, repair, and info on causes of a P079D transmission code which indicates there is slip detected in the D transmission friction element.

Symptoms of P079D OBD II Trouble Code

  • Uneven handling
  • Transmission slipping
  • Erratic shifting
  • Abnormal shift patterns
  • Harsh shift selection
  • ATF (Automatic Transmission Fluid) leak
  • Low torque
  • Abnormal power output

Common Causes of P079D OBD II Trouble Code

  • Low ATF
  • Worn friction element (internal)
  • Dirty ATF Causes
  • Wiring issue (e.g. open, short, chafe, heat damage)
  • Uneven tire sizes
  • Issue causing uneven rotational speed/circumference (e.g. low tire pressures, brake stuck on, etc.)
  • TCM (Transmission Control Module) issue
  • ECM (Engine Controls Module) issue
  • Water damage to module and/or harness

Severity of P079D OBD II Trouble Code

As explained earlier, this isn't something that I would leave unattended, especially if you are actively using the vehicle with said fault(s) present. You should definitely prioritize this. Well, if driving your vehicle is a necessity, daily.