Help with ECU connector pinout
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Driver School Candidate
Joined: Jan 2009
Posts: 14
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From: NJ
Help with ECU connector pinout
Hoping someone here can give me a hand. I am rebuilding a 2017 RC-300 F Sport salvage vehicle and had to replace the ECU that was damaged in the accident.
Two wires one the front most ECU connector (the ECU connector nearest the radiator) were pulled out of the connector and despite reviewing all 198 pages of the RC wiring diagram I cannot locate a
ECU connector pinout. There is a all black wire that resides on one of three pins in the upper left hand corner of the connector (one of the 2 top row left hand pins or leftmost pin in row just below the top row) and a white wire with black stripe that resides on one of the two lower left hand pins of the same connector. If anyone is brave enough to open their ECU box and take a look and confirm where these two wires go I would very much appreciate the help. You don't need to pull the connector, just look at and note where the wire s are inserted in the connector
I've attached a picture of the damaged ECU pins. The left hand side is towards the radiator.
Thanks for any help anyone may be able to provide.
Two wires one the front most ECU connector (the ECU connector nearest the radiator) were pulled out of the connector and despite reviewing all 198 pages of the RC wiring diagram I cannot locate a
ECU connector pinout. There is a all black wire that resides on one of three pins in the upper left hand corner of the connector (one of the 2 top row left hand pins or leftmost pin in row just below the top row) and a white wire with black stripe that resides on one of the two lower left hand pins of the same connector. If anyone is brave enough to open their ECU box and take a look and confirm where these two wires go I would very much appreciate the help. You don't need to pull the connector, just look at and note where the wire s are inserted in the connector
I've attached a picture of the damaged ECU pins. The left hand side is towards the radiator.
Thanks for any help anyone may be able to provide.
Last edited by jmd_forest; May 23, 2019 at 07:10 PM. Reason: clarity
Thread Starter
Driver School Candidate
Joined: Jan 2009
Posts: 14
Likes: 4
From: NJ
I think I've cracked the code!!!!! The System Wiring Diagram (1853 pages long) notes the ECU connector I am interested in as "A70" and numbers the pins in the connector. Searching for A70 in the System Wiring Diagram notes A70 as connector (A) on a "bus" with multiple connectors with wires connected to the bus each with a connector designation and pin. After a couple dozen searches I managed to pin out most of the wires going to pins on connector A70 from the System Wiring Diagram and the remainder from the Overall Wiring Diagram (198 pages). It looks like the White wire with black stripe goes to pin 1 and the black wire goes to pin 27.
Tomorrow I try connecting up Toyota/Lexus Techstream software via a mini VCI cable to pair the key with the immobilizer and write the VIN number of the car into the used ECU. Fun times!
Thanks to all who viewed.
Tomorrow I try connecting up Toyota/Lexus Techstream software via a mini VCI cable to pair the key with the immobilizer and write the VIN number of the car into the used ECU. Fun times!
Thanks to all who viewed.
Lead Lap
Joined: Oct 2014
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From: ON
^^ That is quite an ambitious project and while I couldn't help you even if I tried, you have won a "brave person" award in my books for your work...that is some impressive! I am barely able to open the hood! (lol)
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Driver School Candidate
Joined: Jan 2009
Posts: 14
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From: NJ
I've been rebuilding salvage cars for about 30 years; primarily high end late model low mileage vehicles. This one was hit high in the front driver side missing the frame rail but crunching up the front wheel well and shock tower. Of course that's where the ECU and fuse box sit. One might think it is a devilish plot by Lexus to sell more ECUs as $1200 a pop.
I've already replaced the wheel well and shock tower, radiator, condenser, bumper bar and a bunch of plastic and just finished installing and reprogramming a used ECU and got the car started for the first time yesterday. A little body work and paint on the one old and one new fender and a used hood and new front bumper cover and I'll be about ready to start bolting on the gingerbread.
I've already replaced the wheel well and shock tower, radiator, condenser, bumper bar and a bunch of plastic and just finished installing and reprogramming a used ECU and got the car started for the first time yesterday. A little body work and paint on the one old and one new fender and a used hood and new front bumper cover and I'll be about ready to start bolting on the gingerbread.
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