TCCS ecu questions.

[V8RRolla]

Ok, I'm building a new harness for a 1uz conversion with a TCCS ecu that won't be using the TCCS functions or the automatic. I've heard second hand that the tccs ecu isn't happy without a speed signal, what's the real story on this? I had an old thread about this but that's from before I had the harness and was thinking it was an ls400/celsior ECU. Also, while unpinning everything I noticed two wires that arn't in the ECU pinout I have that were shielded from RF. They are in connector e10 67 and e10 68. I don't have anything past the firewall so I can't tell what they are going to.

Here's the pinout I have if anyone is interested.

 

[V8RRolla]

Well, I was going to just edit the previous post but the button disappeared. On the TCCS ecu if I jump switched power to the NSW input on the ecu will just think its in neutral all the time, does that 4000rpm limiter get enabled when the neutral switch is made?

 

[V8RRolla]

Finished up the wiring harness until it goes into the car. Figured this might generate some interest in this thread.

SC400 ecu, harness was cut at firewall. Decided to just start over instead of trying to solder 60+ wires together.

 

[cribbj]

Looks like you're having fun there with your rats nest. It's a bit late, but FYI in the future if you need an ECU fly lead, try Richard Welch at AutoSport Wiring: www.autosportwiring.com. He does really good work, and isn't that expensive. If you check my supercharged Supra thread, you'll see an example of his work. Don't judge his work by my rat's nest wiring job, however....

On your NSW question, I believe the sole purpose of that input is to inhibit starting unless the car is in neutral, or in the case of a manual tranny, the clutch is disengaged. I don't believe it has any rev limiting functions at all.

 

[V8RRolla]

Wow, Autosport is like... 10 minutes from my house. I've got it handled either way and I've only got maybe $280 and a weekend into it. That's using ETFE Tefzel aircraft wire too. Pretty much every wire is done in that harness except for the shielded wires like knock sensors and cam/crank position sensors. Still waiting on that wire to get here. Should mention this is the 4th harness I've done for a car, first from scratch and 2nd flying lead, I think I'll be fine with it. Also do industrial motor controls wiring occasionally at work, most of the trunk cables coming into those cabinets have more wires than this harness did originally.

As of right now I have the NSW switched on with the start circuit, I think this is correct, I'll leave it until I find out otherwise. I would kill for a i/o logic diagram of the ECU.

Post #11 and #12 of this thread are what got me concerned, it may just turn out that I'm way confused on what those two individuals are trying to do.

http://www.lextreme.com/forums/showthread.php?t=1439&highlight=%22speed+sensor%22

 

[cribbj]

Richard is a technician for a major US carrier, so all his wiring is aero quality. He got started a few years ago doing knockoff Fields jumper harnesses for the Supra market, and his were so much better than the OEM's harnesses that he branched out and built more stuff. Really a nice guy too.

Logic diagrams would be good, but once you've been around the Toyota family for awhile, most of what these signals are and do start sinking in. Toyota are very good about keeping the names of signals and their functions consistent. Plus there are usually some writeups in the service manuals about the various signals, what they do, what the levels should be, etc.

If you're doing this as a sideline, you might consider a subscription to the Toyota TIS system. It gives you online access to all Toyota documentation.

About those posts, if Kdog wrote it, you can take it to the bank.

BTW, I see you have Rolla in your nickname; did you go there? I graduated in '72. Go Miners & happy belated St. Paddy's Day.

 

[V8RRolla]

No I didn't go to UMR, good school though. The name comes from the 1uz ae86 Corolla swap I'm doing for a friend. I picked up a lot of my wiring stuff when I went to University of Texas at Arlington although I put a stand alone in my first car 6 years ago. Did Formula SAE there for a few years where I picked up thousands of hours machining, few hundred hours TIG welding and countless hours wiring. We used nothing but top notch Deutch aircraft connectors and Tefzel wiring, seems to be awsome stuff. Better be if its in aircraft all over the world.

Logic diagrams would be neat just to see how different sensors are utilized by the ecu, I know what all the sensors do and how the output their signals, maybe I'm just spoiled because of the logic diagrams I have for motor controls at work.

As far as fooling the ecu I think i'm going to go ahead and build that square wave oscillator to to a 12v square wave at 1.3 Khz. That should make the ecu think that its going 30mph all the time. I'm not sure if that's going to pose other issues.

Really, I'm hoping I won't even have to use that oscillator box since I'm not going to be using the tccs throttle body with that gay ass 2nd throttle plate. It might just cut spark though. Either way I'm sure I'll get it figured out, I'm almost done with my EE degree, maybe I can use some of that knowledge.