1UZ ECU Identity + Code 47

**CrUZida** · 19-05-2009, 06:05 PM

Originally Posted by jzk25

With the Aristo ecu(same setup) you can just wire up the power and earth and run the signal staright to the ecu.

Interesting you say that, because according to the JZA80 diagnostic book thats the exact signal it needs.

Where as I've wired up UCF10, UCF11 and UZZ30 ecu's to the old style (which is an earthing of the SPD signal 4 times per revolution of the speedo cable) and I haven't seen a code come up, so its obviously worked?

**GreyBeard** · 19-05-2009, 06:59 PM

Originally Posted by CrUZida

Yes, yes and yes.

The car is still shifting because the primary sensor (SPD/SP1, from the speedo) is still working.

Unplug the speedo and you'll see the box do wierd things.

So the speed sensor #1 would be the 3 wire...
I'll have to recheck, i think only used a single speed sensor
probably be weekend or next week.

**CrUZida** · 19-05-2009, 07:16 PM

Yeah the main sensor is the 3 wire one that drives the speedo (which inturn drives the ecu input). Its the main one because assuming the speedo is correct, the ecu will know what speedo you are doing.

The 2 wire one is a backup sensor, which is uses when the main one fails (but it will throw a code if its not working). All that measures is the speed of the driveshaft, which obviously will vary depending on the diff ratio, tyre size, etc.

The 2 wire one needs no extra wiring if you are using the proper loom/ecu/gbox combination. Its all prewired in the loom, straight from the sensor to the ecu.

**CrUZida** · 19-05-2009, 07:18 PM

Ahh shit.
I just looked up code 42, and its PURELY for the speedo sensor, NOT the backup sensor.

Code 61 is the backup sensor.

**jzk25** · 19-05-2009, 08:10 PM

Originally Posted by CrUZida

Kickdown switch is def not required.

It takes a lot of effort to even activate the switch in a Celsior.
(its a very stiff button and needs a fair amount of pressure).

It was definitely required on the UCF11 setup I fitted to the tonner. It would not kick down without it. The TV cable was tensioned correctly etc but the auto was just lazy. Hooked up the switch and it was perfect. Perhaps lack of spd1 in that car was a contributor.
I didn't wire it in(it was years ago and I had no info at the time) and the owner was happy with the car so it never happened.

I also used VDO speedo and tach in the tonner and just used the SPD2 signal to drive it so spd1 never seemed a necessity. The owner thought the UCF11 driveline was a dream compared to the horrible straight GRA gas 350 chev that was in it.

Interesting thing on the subject of electronic aftermarket speedos, in my 2JZ crown I am using an autometer speedo and it actually has an SPD out signal for the ecu so it will recieve a waveform signal and run off that and then also output a squarewave signal for the factory ecu. Handy feature, probably wouldn't keep a cranky toyota ecu happy though.