P1784: Transmission Mechanical Failure - First And Reverse

MediumPowertrainTransmission

What does P1784 mean?

P1784 is a diagnostic trouble code indicating "Transmission Mechanical Failure - First And Reverse". This code relates to your vehicle's transmission and should be diagnosed to determine the root cause. The severity level helps indicate how urgently this should be addressed.

Common causes

  • Low or degraded transmission fluid
  • Worn clutch packs or bands
  • Faulty shift solenoid
  • Wiring issue to the transmission control module
  • Failing torque converter

What should you do?

Schedule a diagnostic appointment at your earliest convenience. The vehicle is generally safe to drive short distances, but the underlying issue should be addressed to prevent it from worsening.

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Code P1784 can mean different things depending on your vehicle. TorqueBot gives you a diagnosis specific to your make, model, and year.

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Related codes

P1783Transmission Overtemperature Condition
P1785Transmission Mechanical Failure - First And Second
P17863-2 Downshift Error
P17872-1 Downshift Error