Camry Auto Trans + Cruise Control Issue

[MWP]

Hi all,

I have an old VZV21R Camry Auto ('89 2.5L V6 2VZ-FE) for my daily while the GT4 is off the road.

I want to get this odd cruise control + auto trans issue fixed before i drive to Melb for the F1 in a week or so.

With the cruise control off, the auto trans works like it should, no probs.
When the cruise control is enabled, the car will immediately shift out of overdrive, and stay stuck in 3rd or lower.
As soon as cruise control is disabled, itll shift straight back into overdrive.

Obviously this makes the cruise control pretty much useless at the moment

This is my first auto trans car, so i dont know a huge amount about how they work.
Anyone have any ideas as to why this is happening??

Thanks!

[wilbo666]

The cruise ECU has the ability to tell the Engine/Trans ECU to drop out of overdrive if it thinks there is a need... like a big hill...

The engine/trans ECU pin for this is OD1.

Perhaps the transistor in the the Cruise ECU is blown and always ON...

As a temp solution you could try disconnecting the OD1 pin from either the Engine or Cruise ECUs and see if this fixed your problem

Btw you sure it isn't a VZV21?

Wiring diagram for a 90 model that might be the same from the internets...
http://www.playnice.org/pdf/Toyota%2...ual/90_EWD.pdf

Cheers
Wilbo

[MWP]

Yup, its a VZV21

Ill put a meter on the OD1 pin to find out what its doing.
Ill try exactly your solution if it is the issue.

Thanks a lot for that!

[MWP]

Quick follow up... cutting the OD1 wire at the cruise control comp did the job

[wilbo666]

Quick follow up... cutting the OD1 wire at the cruise control comp did the job

Good to know, that's what I expected

Next thing on your list should be to work out why



Cheers
Wilbo

[MWP]

I doubt ill revisit it.
Half the under-dash aircon system needs to be removed to get at the CC computer.
As it was i was lucky to get access to the wire to cut it.