Can we do this? (aka The DIY Cruise Control Thread)

[nickhjort]

Is your 07 the same PK198105? I wonder if you have the wiring under the dash unlike mine. If not, what would you do? Say oh well, hang up the towel? I really want this cruise cause I drive to work back and forth about 45 mins each way. It would be really helpful. I mean I'm pretty confident in my wiring abilities. Solder, heat shrink, etc. But of course I don't wanna fuck anything up so bad my dash is gunna end up like that guys in Australia I saw on here today.

[nickhjort]

Cool. Well we'll see tomorrow then.

[nickhjort]

I see, I see. One other quick question. If I don't have all the wiring for this from the ECM, do you think I will have to do anything to get the brake switch to work, or will it already be programmed to turn off the cruise control when I hit the break? And I didn't see the plug for the clutch switch near where the switch goes...will I have to wire that once I buy the actual switch and take the jumper out?

[CTScott]

Originally Posted by nickhjort

I see, I see. One other quick question. If I don't have all the wiring for this from the ECM, do you think I will have to do anything to get the brake switch to work, or will it already be programmed to turn off the cruise control when I hit the break? And I didn't see the plug for the clutch switch near where the switch goes...will I have to wire that once I buy the actual switch and take the jumper out?

If your Yaris has the brake switch, then your OK, as there is only one.

For the clutch switch, if this works, then you'll have to snake a wire from the under hood fuse box to the clutch switch and wire it yourself.

[CtrlAltDefeat]

The more I read, the less i want to do this lol Maybe if someone does it and gets it right with a good diy...

[nickhjort]

That's what I'm saying now :) I might wait and finish after someone smarter than me does it and includes nice pics to follow haha!

[MGargano]

Ditto for me. I have the 09 and bought the OEM stalk, but mine's a 5 spd. so I'm worried about the clutch switch install

[CTScott]

Oh, and the white that you jumper the clutch switch wire to is indeed the one I meant, so you're OK there...

[nickhjort]

Ok i see that now that I look at the pic. You had one more white one in with the brown one huh? And I see I was looking at the wrong side of the connector...duh. Anyway I'm gunna try that other pin in the ecm and try again tomorrow. Thanks a lot we'll see what happens :)

[CTScott]

Originally Posted by nickhjort

Ok i see that now that I look at the pic. You had one more white one in with the brown one huh? Anyway I'm gunna try that other pin in the ecu and try again tomorrow. Thanks a lot we'll see what happens :)

Sorry about the confusion on that. I didn't realize until I dropped the pic on the computer that the white I meant was hidden and the other white was right there in the foreground.

I was just tracing the 7.5A IGN fuse and I think that the pin you are on, on the ECM, is hot, so when you hit the switch it grounded it and popped the fuse, as that fuse feeds parts of the ECM.

By the way, before you road test with the correct pin, try the ON button in the driveway to be safe. I can hit the on with the ignition on and engine off and the cruise light comes on. Obviously you won't be able to tell if cruise is actually working, but at least you'll know if you pop a fuse.

[CTScott]

Awesome! I'll design a circuit for the LED. It will probably require changing the on/of switch to a DPDT switch, as the LED circuit will have to be controlled by the switch, rather than the ECM.

[CTScott]

Originally Posted by PK198105

Scott why not just take an OR gate and use that for the LED. Or a simple 2N2222 transistor setup as a switch.

The circuit needs to be a bistable flip-flop.

[nickhjort]

You don't think the wires going to the speedo and stuff has the cruise wire in it even though I don't have cruise indicator...? That would be much easier :)

[CTScott]

Originally Posted by nickhjort

You don't think the wires going to the speedo and stuff has the cruise wire in it even though I don't have cruise indicator...? That would be much easier :)

Unfortunately not. The microcontroller for the combination meter gets the cruise status from the ECM over the CAN bus.

The only possibility that I can see is that the microcontroller appears to drive all of the status LEDs via a 4-bit multiplexer. It is possible that the micro is programed to support the LED, but has not connection to it. If you want to disassemble your meter and take some pictures of the PCB I can take a look.

[nickhjort]

I can take some pics tomorrow. You need the back or front of the circuit board? I might see how hard it's gunna be to change the led's while I'm at it. Change the colors of my speedo and stuff.

[CTScott]

Originally Posted by nickhjort

I can take some pics tomorrow. You need the back or front of the circuit board? I might see how hard it's gunna be to change the led's while I'm at it. Change the colors of my speedo and stuff.

Both sides if you can get at them. If not, some good macros of the IC's so I can figure out what they are and the pinouts of them.

[nickhjort]

Damn, thanks for doing all this $hit man. I'll get the pics for ya tomorrow.

[mrbond]

Alright, so to make the OEM stalk work, how would it be different than what nickhjort is doing?