Bad ecu question
#16
Lexus Test Driver
iTrader: (27)
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You would need all three, the security ecu, engine ecu, and keyfob from the same car the engine ecu originally came from.
Hopefully the battery has been disconnected while you did all that swapping. If not you may need the locksmith to come out anyhow.
Unplug the battery for 20-30 min and try again..
What was the problem you were having with the ecu in the first place? they rarely go bad.
Hopefully the battery has been disconnected while you did all that swapping. If not you may need the locksmith to come out anyhow.
Unplug the battery for 20-30 min and try again..
What was the problem you were having with the ecu in the first place? they rarely go bad.
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#17
Lexus Champion
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There is no security ECU. The engine ECU handles security as well. See that attached for parts location.
When you inserted the key and the security light didn't go out, that says 1 or 2 things. 1 that is not the right transponder and/or, if it is the right transponder, the code is not received by the ECU.
You can look here for diagnostic tips and additional info. It's under engine immobiliser system. This is in the GS FAQ.
http://bahamutcars.free.fr/workshop/...nts/index.html
When you inserted the key and the security light didn't go out, that says 1 or 2 things. 1 that is not the right transponder and/or, if it is the right transponder, the code is not received by the ECU.
You can look here for diagnostic tips and additional info. It's under engine immobiliser system. This is in the GS FAQ.
http://bahamutcars.free.fr/workshop/...nts/index.html
There most certainly is an additional ecu for the immobilizer system.
Sorry I did not call it by the correct name. It is technically the 'Transponder Key Amplifier' and it is what gets reflashed.
I have fist hand experience with this on an aristo immobilizer ecu swap I did. And a mobile toyota locksmith re-flashed it to pair with the new engine ecu.
The keys internal transponder does not send a code directly to the ecu, it simply ok's the Transponder Key Amplifier to send the start signal to the engine ecu. But if the new engine ecu has not been paired to the existing Transponder Key Amplifier then it won't allow it to start.
It holds all the immobilizer programming and handles the communication between the car, the key, and the engine ecu. The engine ecu cannot be flashed, nor would it ever need to be..
Last edited by 99 GS3; 03-23-12 at 02:29 PM.
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jehmin
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