The Toyota Previa in China, also known as the Toyota Estima in Japan, and Toyota Tarago in Australia.

If the car owner have master key, manual add key is workable, if all key list, can’t add keys directly with universal key programmer, for non-smart key fob, only need to reset immo box to virgin, for smart key fob, need to reset immo box and smart box. With Toyota Previa 2010 model smart system, below are the steps to add keys if all key lost.


Step 1: Reset immo box. Disassemble immo box NO. 89784-28011 which placed in a groove in the back of evaporator under the dash, open box and find the EEPROM chip 93C46 on the board, read the chip by key programmer like Yanhua key mater, VVDI prog etc. Save the data and backup. Modify the data like this: replace the bytes in blue area with 0, this area is the quantities of keys, reset is to make it to learn keys, zero means no key, need to learn new key. Red area is the data synchronizes with engine, retain. Other bytes all replace with F. Save the data and write it back to chip 93C46.



Step 2: Reset smart box. Disassemble smart box No. 89990-28131 located near A-pillar behind glove compartment. Open the box and find the EEPROM chip 93C86 on electronic board. Read the chip with key programmer. Save data and backup. Modify the data like this: retain Blue area, other bytes all replace with F. Save the data and write it back to chip 93C86.



Step 3: assemble immo box and smart box back to car, go in car and push start button, the dash will be lighted, it’s an indication that you can use key programmer to add keys.

Step 4: connect key programmer with car OBD to add keys. Select Toyota smart system, follow the software steps to make key fobs held close to start button, comes with “beep beep”, that is we add keys successfully. No need to do synchronization, just start the car. Finish.


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