DIY Cruise Control on 07-08 Yaris (step by step)

[CTScott]

Originally Posted by goat1of2

And yet *another* new Yaris owner gives this a try......

It seems that y'all are saying that we should disconnect the battery before pulling off ECM connector A21. Yet, won't I need the battery connected to check if 12V is present at pin 40? That's right, I've never messed with the electronics in a car before.

Also, I'm looking at the document so kindly provided by Vince87 and I cannot for the life of me find Connector D3 either. I have a very late model 2008 and wanted to make sure that the wires I need aren't already in the cabin. There's a whole passel of connectors under that dash, most of which I cannot see because of all the plastic covers. Do I need to remove some of them?

Check out this link for a comprehensive list of links related to installing cruise control:

http://www.yarisworld.com/forums/sho...ght=cruise+faq

This picture from my 09+ DIY shows D3 (the leftmost connector with the brown, blue and black wires):



You need to remove the lower steering column cover to gain access to it.

As far as disconnecting the battery goes, you should do so while doing the wiring to the ECM. Checking for 12V on pin 40 is really only necessary if you have issues with it not working, and in that case, you'd measure the voltage at that pin via the wire that you connected to it.