DIY: Immobilizer Hacking for Lost Keys or Swapped ECU
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wmj259 (07-05-18)
#18
Intermediate
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Seems like when applying 5V to it, it activates the board, so it requires the crystal to be shorted so it can't make timing.
Last edited by wmj259; 07-05-18 at 08:15 PM.
#19
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There were 3 crystals on my board. I tried shorting each individually and all at once to program the board. After I pulled the chip off and got it soldered to my programmer it worked really easy.
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wmj259 (07-06-18)
#20
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I'm new to this page but I have a question about this process. First off I have a 2000 es300 I only got one key with the car when I bought it. Now I lost my key now I'm woundering if I went to my local pick n pull found the same gen car with a key if I could switch out the ecu the ring the ignition and all the fixings for the immobilizer system if it would work turn key after everything associated with this system was replace from a doner car
#21
Lexus Fanatic
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That will work but you'll need to swap the ECU with the same part number.
#22
Intermediate
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I just soldered the eeprom chip back onto the board but only have access to 2 of the 3 keys I have. Would reprogramming the 2 keys to the new ecm work? The second would just be registered as a valet right?
#23
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They will both be master keys. The third one will be a valet. If you dont have a third it will stay in registration mode until either shut off with techstream or a few cycles of the key. There may also be a way to do it by stepping on the brake pedal like 5 times real quick. A few answers on google. I used techstream.
#26
Intermediate
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I am not sure now if its in registration mode. It has been 5 minutes now, I will probably have to clear the eeprom again.
The first key I used was the original master key. I locked the door, unlocked the door, inserted key into ignition and did not turn, waited 15 seconds, removed original master key, inserted my new key, did not turn, waited 15 seconds, pressed the brake 5 times. Reinserted master original key into ignition and the security light lights up for 3 seconds, and then turns off. The new key, the security light keeps blinking.
I know both keys worked for my old ecm.
The first key I used was the original master key. I locked the door, unlocked the door, inserted key into ignition and did not turn, waited 15 seconds, removed original master key, inserted my new key, did not turn, waited 15 seconds, pressed the brake 5 times. Reinserted master original key into ignition and the security light lights up for 3 seconds, and then turns off. The new key, the security light keeps blinking.
I know both keys worked for my old ecm.
#27
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I didnt do all that. I made sure my battery was unhooked, plugged in and mounted ecu, made sure key is out of ignition, hook up battery. Now get in and shut door, insert key and remove, security light should stay on. Reinsert key, light should flash a few times. Leave key in 15 sec, remove and insert next key leave 15 sec then same for last key.
#29
Intermediate
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Well, after removing the ecm, reading the chip, I moved the valet key numbers into the master key slot #1, and filled the other two key slots with the dummy numbers from speedkars number dump. Now when inserting the original master key, the security light goes out.
Now I'll just reprogram the other 2 keys in.
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Last edited by wmj259; 08-12-18 at 09:29 AM. Reason: spelling "valet"
#30
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Well, after removing the ecm, reading the chip, I moved the valey key numbers into the master key slot #1, and filled the other two key slots with the dummy numbers from speedkars number dump. Now when inserting the original master key, the security light goes out.
Now I'll just reprogram the other 2 keys in.
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wmj259 (08-11-18)