Sigma EV button installed

I just finished installing the Sigma OEM EV button in my '07. It didn't go quite as smoothly as I would have liked, mainly due to the business about having to scavenge the proper terminal for the connection to pin 27 in the ECU. But I got through it and it works! I'm posting here to highlight 3 main points:
1. To share my experience with the various sets of instructions I used.
2. To highlight a potential pitfall associated with making the connection to pin 27.
3. To find out if anyone has gotten the EV indicator light on the instrument cluster (not to be confused with the little back-light on the button) to work with this mod.

Point 1:
I started with the install instructions for the Sigma EV button posted on the LIPOG website. These are a combination of instructions previously posted elsewhere. But they were a great start. The problem with the Sigma EV button is that one of the 5 terminated wires that is supplied has the wrong type of termination on it. This is the one (blue wire) that is intended to make the connection to pin 27 in the ECU. This issue is highlighted in the instructions, and the solution provided is to scavenge a termination from a connector inside the steering column that makes the electrical connections to the turn signal controller. The instructions on the LIPOG site didn't show how to get at that connector. But with a little searching, I found some excellent instructions for this step on the calcars site. This was enough information with excellent detail to be able to do the install. After completing the installation I also viewed Thunder's Prius EV mod and install commentary video which shows how to do the Coastal EV switch mod. He did an excellent job of spelling out the ECU pin 27 situation, which I think actually poses more of a risk with the Sigma EV install than with the Coastal. Which brings me to...

Point 2:
Although I don't have any direct experience with the Coastal EV switch install, I can tell from Thunder's video, and the subsequent posts from others that Coastal did a great job of providing exactly the right components to do the job quickly and efficiently. - Not true for the Sigma EV button. This business about having to dig a termination out of the turn signal indicator connector inside the steering wheel stalk is for the birds! Sigma really should provide the right terminated wire with the button when they sell it. The blue wire they do provide has a termination on it that doesn't fit any connector relevant to this install, as far as I can tell. This was clearly an oversight that should be corrected (if it hasn't been already).

I successfully got the little termination out of the turn signal connector inside the steering wheel column and fasioned my own little terminated wire. The calcars instructions cover that in detail. They soldered the wire to the termination, but mention that the termination is actually designed to cut the wire's insulation during crimping in place to make the connection that way. The problem for me came when I installed it into pin 27. Thunder covers that part nicely in the video. When he describes how you need to use the jeweler's screwdriver to help push the terminated wire into the connector he cautions to take care not to damage the wire, and says "that would be a situation I wouldn't want to be in". Well... that's exactly the situation I got "in". The wire I used to fasion my pigtail was probably a little thinner than it should have been, and my termination piece may have required a little more force to get it all the way into the connector than it should have. And I found myself with the terination pushed all the way into pin 27, and the wire loose in my hand. That's one of those "Oh Sh*t!" moments. - Put all cutting tools down, and THINK for a few minutes. <_< I managed to get another wire (larger single conductor, not stranded) to fit and hold into the end of the termination inside the connector. But I fear that it won't hold up over time/vibration. I'll probably be back in there at some point trying to improve that connection. I'm open to any brilliant ideas on what to do about that.

My caution to anyone out there doing the Sigma EV button install is to make sure the pigtail you put together is robust, and that the little termination piece is not deformed in anyway that it might not want to slide smoothly into pin 27 of the ECU connector. And, you want to be very careful pushing it all the way in. It will very likely need some help from a little tool. But you want to make sure not to damage it. Of course, I don't blame Sigma for my mishap here. - Having been through it once, I know I wouldn't make that mistake again. But in this case, you really only get one shot. And, I'm pretty sure it wouldn't have happened if I had the right component from the start.

With all that said, I still like the OEM EV button location, look, and feel over what I've read and seen of the Coastal EV function in the cruise control stick. That's a personal preference though. But the Coastal folks sure did a nice job identifying and including all the needed components (down to the tap connectors) in the kit they provide, as far as I can see from Thunder's video. Another nice thing about the Coastal EV install is that you only need to open the dash on the passenger side. - As opposed to the Sigma OEM EV install where you need to open up the dash on both sides (oh yeah - and the steering column - for parts).

Point 3:
In the instructions on the LIPOG site there's some text describing operation of the EV function that says -

"Press the switch to turn on the electric motor power manually. The indicator light in the instrument cluster comes on. Pressing the switch again will turn off this function and the indicator light."

This came from an English translation from the Japanesse user's manual describing the operation of the EV function. So my point here is - I don't see the EV light come up on the instrument cluster when I put the car into EV mode. Also, I haven't read or seen anything from anyone here who has done an EV mod that indicates that they've gotten that light to come on. I know the light is there because I recall seeing it come up during some crazy state when all the lights lit up - I think it was when I ran out of gas, and I got that big red exclamation point.

Does anyone who's done the mod get the EV light on the instrument cluster? If so, how'd you do it? If not, I think we're missing a connection here that we could probably make to get that to work.

To sum it up - it's pretty cool to be able to hit that little button and prevent the ICE from coming on. At lunch time I like to go to a gym that's about 3/4 of a mile away from my job. The button will drop me from 4 to 2 engine warm-ups per day on those days. I'm guessing that will make a difference in my overall mileage.

 

<div class='quotetop'>QUOTE(comtech5 @ Apr 29 2007, 07:32 PM) [snapback]432243[/snapback]</div>

Hmmm. I could have sworn I saw it on there the one time I ran out of gas and all the instrument lights lit up on me. I recall it having the little car shape with "EV" in the middle of it - very similar to what's on the button. And I could be off-base on this - but I think it actually stayed lit when I drove the half mile or so to the gas station on battery power. I'm having trouble trusting my memory though. That was right before they brought me up on the spaceship and performed experiments on me.

- Just kidding about the spaceship (and the experiments) part. But I do think the rest is accurate. I don't know how to simulate that again without actually running out of gas. And I don't really want to try that.