WrenchTech
New member
All 1999-2000 4Runner 5VZ ECUs have that plug, regardless if your vehicle came with an immobilizer or not. There are no ECUs made specifically for vehicles with an immobilizer, the immobilizer is a completely separate entity in the vehicle and all the ECU does is store the coded values the immobilizer checks. So if your 4Runner does not have an immobilizer, this new ECU won't care and should run normally.
Thanks for that info. I was trying to figure the whole thing out by looking at Toyota parts dealer catalogs. I know they call for a different ECU for late 99 4runners and another one for early ones (thru 5/99) It also looks like they replaced several different ECUs that they were offering for 97,98 and early 99 models with a single unit. I thought I was going to have to sell the one I got with the transmission and look for the correct one, but if this one works I’ll be a happy camper. I have the factory electrical service manual and I have been studying it in preparation for my transmission swap. I find it amazing to see how much more complicated the electrical systems have gotten since the first and second generation. They have what they call ECUs scattered all over the vehicle. An ABS ECU, a moonroof ECU, a cruise control ECU, a body ECU, etc. And then they have the small subset of devices that consist of taillight, daytime running lights and a few other things connected in what is called the multiplexing system. In spite of all of that I have not figured out what I have to do with the two switches on the clutch pedal and the reverse light switch on the transmission.
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