4Runner ECUs

[Koz]

I counted 23 ECUs (electronic control Units/computers) in my Limited 4Runner. Some of the interesting ones are; Body ECU, Suspension ECU, Back Door ECU, Multiplex comm. System ECU.

Koz

 

[greasefingers]

I have done a lot of research and studying the ECU on my Jeep; by reading the electrical schematics. I do not know if they all function by the same principle, but the Jeep ones are basically something I call switching-ground units. All of the sensors and actuators always have power but the ECU grounds them so juice can flow. Other than that, they store data curves for things like the shift points for the tranny and make decisions like how long to keep the injectors open from the various Inputs from many sensors. My Jeep only has two ECUs: one for the tranny & one for the engine controls, but it was made in 1994. I guess it makes more sense to have several ECUs since you throw them away if something burns up like a transistor or a capacitor? I also suppose that many circuits have been replaced with IC chips?

 

[ksneubec]

I counted 23 ECUs (electronic control Units/computers) in my Limited 4Runner. . . . . . .Koz

We need to find you some new hobbies . . . .

 

[rando]

Re: Re: 4Runner ECUs

Now that's funny ... don't care who you are!

We need to find you some new hobbies . . . .

 

[Koz]

Excessive

 

[Uneek]

Koz,

Does it mention anything about the ECU learning our driving habits and adapts the truck to our driving styles? If it does, I'll need to reset mine after breaking it in. :

Thanks.

 

[Iowa4Runner]

I have done a lot of research and studying the ECU on my Jeep; by reading the electrical schematics. I do not know if they all function by the same principle, but the Jeep ones are basically something I call switching-ground units. All of the sensors and actuators always have power but the ECU grounds them so juice can flow.

I noticed the same thing with my 4Runner's fuel injectors. That's why I was so careful with my wiring job when I install my homemade corrector for the MPG display. If the wire I tapped into gets grounded on the frame or something, one of the fuel injectors would stay open indefinitely. God only knows what would happen then.

As a rookie switching power supply designer, I like the low-side switching topology because it's simple and straight forward to interface with logic level outputs. Plus you get to use NPN or N-channel transistors, which generally have more desirable switching characteristics.