2009 Toyota Prius BaseFACTORY OEM SERVICE PROCEDURE

Horn System: Notes

PRECAUTION 

NOTICE:

For initialization:

When disconnecting the cable from the negative (-) battery terminal, initialize the following system after the cable is reconnected.

System Name See procedure
Power Window Control System Smart Key System Specifications, under CUSTOMIZE PARAMETERS

For hybrid system activation:

When the warning light is illuminated or the battery has been disconnected and reconnected, pressing the power switch may not start the system on the first try. If so, press the power switch again.

Factory Service Tools

Use the Manual With the Right Hardware

Pair factory procedures with proven DIY tools so the instructions are easier to execute.

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • • You smell fuel, burning insulation, or see smoke.
  • • Brakes feel soft, pull hard to one side, or make grinding noises.
  • • The engine overheats, stalls repeatedly, or misfires under load.
  • • You are missing required tools, torque specs, or safe lifting equipment.
  • • You are not confident in the next step or safety outcome.