MX83 Cruise Control wiring...

[fatboy13]

Hey guys,

Just helped a mate do a manual conversion into his MX83, and now we cant get the cruise control working.

Its a 1J conversion that was obviously auto previously and is now running an R154. Cruise was working fine before the conversion, so what do we need to hook upto where to get it working with the manual?

Thanks in advance

Ben

[CrUZida]

Clutch switch.

[CrUZida]

And some trickery to tell the cruise control its constantly in "D"

[fatboy13]

slutch switch and trickery, can you elaborate please

[big_zop]

I assume that he is reffering to the factory management still being used to control the engine, cruise control shouldnt be too much of a problem. In order for it to work, the ecu needs to know the auto trans is in drive (which needs to be switchable since you would want to start the car somehow). and the clutch switch will be similar to the brake switch, which will deactivate the cruise control upon pressing the clutch.

as for actually getting this to work, will have a look around for some appropriate diagrams, etc, that might help you because ive never actually done this myself.

how have you bypassed the gear position indicator (cant remember the proper name) as i hope you arent trying to constantly run it in neutral?

[fatboy13]

Yeah factory management to control the engine etc during cruise control...

I think its set to constantly run in neutral with some kind of relay, as it needs to be in this to start does it not?

And thanks heaps +rep for joo

[big_zop]

gear position indicator (cant remember the proper name)

Called the Neutral Start Switch.

I assume that he is reffering to the factory management still being used to control the engine

Turns out i was wrong with this. Found out that the Cressida has a separate crusie control computer so it should be possible for you to replicate the signals required to get it to work, provided it wasnt removed during the install. Do you know if it was removed (im not sure where they are located or how obvious they are labelled)?

fatboy13 - you have email too.

[bungs]

Yeah factory management to control the engine etc during cruise control...

I think its set to constantly run in neutral with some kind of relay, as it needs to be in this to start does it not?

And thanks heaps +rep for joo

Just rewire it so the relay is only active when the clutch is pushed down. So when the clutch is pushed in, the car thinks it's in neutral. When the clutch is out, the circuit is broken and hence the ecu thinks it's in drive... Cruise control will work as normal with this setup.

[big_zop]

Just rewire it so the relay is only active when the clutch is pushed down. So when the clutch is pushed in, the car thinks it's in neutral. When the clutch is out, the circuit is broken and hence the ecu thinks it's in drive... Cruise control will work as normal with this setup.

I was thinking of this but would question how it would run as it would also be changing between Neutral and Drive on every gear change.

I dont know the factory tuning but it would be safe to say that Neutral is obviously tuned with no load and would have slightly different fuel/timing to when its in Drive - would be a good dyno test especially if you have a manual ecu to swap too...

And i doubt Toyota would expect too much revving, especially loaded if you constantly trick the ecu to think its always in Neutral.

It would solve the cruise deactivation upon putting the clutch in though.

[CrUZida]

Wire the engine ecu to think its constantly in neutral, wire the cruise ecu to think its constantly in D.
Wire a clutch switch in so that when you change gears it doesn't rev its tits off. A lot of Toyota's already have the wiring for the clutch switch there, you just need the switch. MX83 may be different though.

You can do what big_zop is suggesting, its just a little bit more wiring.



http://conceptual.net.au/~peewee/wir...ical%2006a.jpg

[takai]

FWIW where is the Cruise ECU?

[CrUZida]

MA61 has it in passengers kick panel.
I'd start looking around there.

[takai]

Yeah, aint there. Just a junction box with the COR and another relay. Im betting itll be under the drivers side dash. Enough other little boxes up there.

[Mos]

It is under the driver's dash, IIRC a bit higher and deeper than the central locking ecu.
The other relay in the passenger kick panel is the heater (blower) relay.
Mos.

[takai]

Ah, thanks, i was wondering what that one was. A nice nondescript "Relay" was printed on it, which is bloody helpful.