2JZ-GTE VVTi Getting Cruise Control to Work.

[jzmx32]

Hey all,

I'm chasing some info on getting the cruise control to work again on my crown, hopefully someone has the missing piece of the puzzle for me.

The car is a 2002 JZS171 Crown Estate
The Engine is a VVTi 2JZ-GTE from a 1998 JZS161 Aristo - factory ECU (89661-3A470)
The gearbox is an R154 from a JZX100.

Cruise control used to work with the 1J and the Auto.

I have a 12 tooth diff mounted trigger wheel using the original speed sensor feeding into SP2 at the ECU.

I have the cruise control switch wired to the CCS pin and E1 - the resistance values change when the switch is pressed (on/off, set, reset, etc..)

I have the dual circuit brake switch wired to STP (0v when not pressed, 12v when pressed) and ST1 (12v when not pressed, 0v when pressed)

Pressing the on/off switch does not illuminate the cruise light. Pressing the set switch does not engage cruise at any speed.

I've also attempted go get it to work on the bench connected to techstream, but I only see three parameters in the cruise control live data screen, and they do not relate to the switch positions.





Any help would be greatly appreciated.

Cheers.

[madmont]

Have you told the ecu that it is in drive?

[jzmx32]

I have not done that.

OH man, if it's that simple I'll be very happy indeed.

[madmont]

Cruise control only works in drive

[jzmx32]

madmont,

I had a go at this in the car and on the bench with a spare ecu.

12v to engine ECU pin 'D' brings on the 'D' light on the dash and registers in techstream as the trans being in drive.

The cruise light doesnt come on in the car though and the same three parameters are all that is shown in the cruise control live data.

I seem to remember that with the auto and the that 1J pressing the on/off switch on the stalk would cause the light to illuminate / extinguish, even with the trans in N or P.

Could anyone with factory working cruise confirm this?

Are there any other conditions required for cruise to be enabled?

Cheers,

Ben

[madmont]

Mine works ok.
I can plug in my JZS161 instruments and the cruise light will light up when the button is pushed. The ECT/PWR light also flashes to let me know there is no auto

[jzmx32]

There's gotta be something I'm missing, unless it's related to a mismatch of the crown and aristo multiplex. Like if the crown multiplex isn't seeing the 1j engine ecu and is sending an error out disabling cruise. Or if the 2j engine ecu isn't seeing the aristo body ecu and is disabling cruise. I don't understand how it all works though.

The crown did not come from factory with cruise, however to get it to work with the 1Jand the auto all I had to do was add the stalk and the dual circuit brake switch.

I just noticed a slight difference in the wiring diagram between the aristo and crown cruise systems. It looks like the both circuits of the brake switch in the crown system are open or closed at the same time, whereas in the aristo system they are inverse.

Could be misunderstanding it though. I'll have to double check how mine is wired.

Crown:


Aristo:

[madmont]

No multiplex in mine. I have also wired in a switch on the clutch pedal to cancel cruise .

[madmont]

Do you have 12v on F60 pin 7?

[jzmx32]

Yes, voltage at +BM (F60 Pin 7)

[Tire Shredder]

Madmont,

Did you do anything with the overdrive speed sensor as well, NCO?

Wilbo could never get get his stock VVti ECU to work properly with with just SP2 hooked up.

Do you leave you Drive (D) pin powered all the time?

[madmont]

Overdrive speed sensor is not connected. "drive" pin is always connected.