bypassing imobilizer 98 Avalon

My father recently lost his transponder key for his 98 Avalon. The dealer is saying that without the original key, the entire ECU module must be replaced and paired with a new transponder key. They are estimating over $2000 for parts and labor.I had the idea, that since they sell 555F and 555U transponder by-pass units for use in remote startable cars with imobolizers, it would be much cheaper to install one of these myself. Remote starters go for about 100 bucks, and the bypass unit for around $50.I'm concerened however, that the remote starter only starts the engine to warm-up, and that you'd still need the original transponder key to later restart the car and shift into drive. I do have a correctly cut key to slip into the ignition once the engine is started, but it does not send the proper codes to the imobilizer unit. Get what I mean? I just need the damn ecu to be tricked into letting my good key (sans correct transponder signal) to start the engine. I figure since the by-pass units can do it for remote start, there must be some way around buying a new ECU unit. Does anyone know whether or not this is possible to do with out a working transponder key?

maybe use one of the bypass units and power it off of the ign wire ... hmm, or does it need the original key to crank the car and let it "learn" the code? .. Well Im not sure about Toyota but Ford/Mazda for example keys can be purchased under 20 bucks.

better yet, ifyou can find the right wire that goes from the key cylinder to the ecu you can probably check the resistance on that wire and wire in a resistor ... maybe all of these methods wont work .... i m sure someone who knows for sure will chime in

I have a key cut that will turn the engine, but because it's not sending the code, the engine won't start. Toyota tells me that they can't program a new key without an original (brilliant engineering huh?) and that to make a new key for the car the entire ECU has to be changed. As unbelievable as this is, they seem to be telling the truth according to what I've found on the internet.

you had better try another dealer as the toyota dealer in my area did replace a key for a car that had lost all keys heres a hint call Howard keys 18005249199 and order at least 2 toyota transponder keys theyre only 7.95 each and take them to a hardware store and have them cut to match your non working key most hardware stores will only charge about $2 to cut keys  and go to to another dealer and see what they can do for youtj

The 555F and 555U transponder by-pass units  will not wirk for what you want it to do. These units both require the key that will release the immoblizer for programming or for use with the system. That sounds a bit steep for getting a new setup. I know if you loose a key for a Ford, they just get your VIN number and such from you and they make you a new key but costs only a couple of hudred bucks, not thousands.Jeff

Velocity Custom Home Theater

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Hmm, that's too bad. TJ, what model Toyota was it?

Just a FYI: I've found someone on E-bay who claims he can reprogram your ECU and provide you with a new key, all for $100. I'm thinking about trying this as he has good user feedback on E-bay and I'm willing to risk the hundred bucks and my ecu considering it looks like my only other option is to install a new one.