Safety Warning

DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.

2004 Toyota PriusFACTORY OEM SERVICE PROCEDURE

Smart Key Ecu: Replacement

HINT:

The installation procedures are the removal procedures in reverse order. However, only installation procedures requiring additional information are included.
A bolt without a torque specification is shown in the standard bolt table (see SPECIFIED TORQUE FOR STANDARD BOLTS ).

DISCONNECT BATTERY NEGATIVE TERMINAL
REMOVE INSTRUMENT PANEL FINISH PANEL SUB-ASSY UPPER (See INSTRUMENT PANEL SUB-ASSY )
REMOVE SMART KEY ECU
1. Disconnect the connector.
2. Remove the 2 screws and smart key ECU.
CONNECT BATTERY NEGATIVE TERMINAL
NOTE: When disconnecting the negative (-) battery terminal, initialize the following systems after the terminal is reconnected.
SYSTEM INITIALIZE

Fig 1: System Initialize Table
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

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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.