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P0804

1-4 Upshift (Skip Shift) Lamp Control Circuit Malfunction

● Get it checked quicklyPowertrain · TransmissionGeneric (all cars)
SystemPowertrain
GroupTransmission
SeverityGet it checked quickly

What does P0804 mean?

P0804 stands for 1-4 Upshift (Skip Shift) Lamp Control Circuit Malfunction. The transmission control system has found a problem. You may notice harsh, late or missing gear changes.

Powertrain codes cover the engine, transmission and emissions. When the car's computer sees a reading outside its normal range, it stores this code and may turn on a warning light on the dashboard.

Common causes

  • Low or old transmission fluid
  • Faulty shift solenoid
  • Faulty transmission speed or temperature sensor
  • Damaged wiring
  • Internal transmission wear

What to do

  1. Read all stored and pending codes with a scanner. Several codes together often point to one cause.
  2. Note the freeze frame data (speed, temperature, load) recorded when the code was set.
  3. Inspect the wiring and connectors of the part named in the code for damage, corrosion or looseness.
  4. Fix the most likely and cheapest cause first, then clear the code and drive to see if it comes back.
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Frequently asked questions

What does P0804 mean?

P0804 means “1-4 Upshift (Skip Shift) Lamp Control Circuit Malfunction”. It belongs to the transmission group: The transmission control system has found a problem. You may notice harsh, late or missing gear changes.

Is it safe to drive with P0804?

Avoid driving long distances. This kind of fault can cause damage or affect safety, so get it checked as soon as possible.

How do I clear P0804?

Fix the cause, then clear the code with an OBD2 scanner or app. If the fault is still there, the code will come back.

Related codes

Code meanings can vary by manufacturer. This page is general guidance, not a repair manual. Always confirm the cause before replacing parts.

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