Ok.... so back in 2009 I found that Isis Power (
http://www.isispower.com/ ) released a multiplex kit to replace traditional wiring harnesses. I was very intrigued, but had already purchased a Painless kit to install in my project. Family happened and I didn't get around to wiring my car till late last year. While the Painless kit worked well, I was a little unsatisfied with the wire routing and had a issue with the ignition switch and my ECU for my fuel injection. I could have solved the issue with just wiring a diode in between the ACCY and IGN contacts in order to keep power to the ECU when starting the car. Believe me, that was the cheep option at less than $2 for the diode.
The ISIS kit was still lingering in the back of my mind and decided to ditch my harness and go for it.
Let me start this by just stating a few things about the company. I did talk to one of their sales people before I placed my order and he was very knowledge able about their system and electronics in general. After speaking with him I decided a week later, to place my order on their site. Notification of my order status was not something that came automatically. I had to call about my order a week after to find the status and found out that some of the components for the kit were back ordered. It so happened that I was talking directly with the owner, Jay Harris. He was extremely personable and helpful on the phone with telling me the situation on the parts and we got everything set up to have the in stock items shipped immediately with the back ordered items to ship when as they came in. This allowed me to get somethings already wired up. I did get email notification of shipments. This being said, if you do decide to go with this setup, call to place your order so you know upfront what that delivery timing is looking like.
The kit:
I ended up purchasing a front engine 3 cell kit, with the inLINK RF control, and a inMOTION Motor controller. As of now I have the Master Cell and the Power Cells installed in my car and wired to all my components that require power. I have no switched wired yet but should complete that by the end of the week. The biggest issue is deciding how to mount those cells to get easy access, and to get clean routing of your wires. I ended up fabricating a several new brackets to mount the cells and the MEGA fuses. Even though I don't have the switches connected yet, I can control the car with the RF control which is pretty cool.
The wiring connectors to the the Master Cell, the cell that all the switched connect to, are very intimidating because each of the two connectors have 30 wires coming out them. It is easy to start thinking "that is a lot of wiring to do!" It is not once you start getting your head wrapped around how the system works. You find out that early half of the wires will not be used and you can simply remove them from the connectors. For instance, on our cars we have single filament bulbs for the tail lights. On the connector there is a specific wire to be used on the brake switch for single filament bulbs. There are others to be used for duel element bulbs. Same for the turn signals if you have a mechanical turn signal switch, like we do, or if you want self cancelling signals. What I have found out is that I will actually have less wire under my dash, than with the traditional harness. I will only have seven wires to connect to my steering column harness!
The other neat thing is that there is no positive power running through any of my switches! The switches are wired to where they are designed to complete the ground instead of to allow the positive power to flow. This combined with the Multiplex cells is what allows for the fewer connection to the steering column. I only need to complete the path for the turn signal to know that the turn signals are to be switched on. I don't need to route the actual power back out of the column to the lights. The system just knows that the front and rear signal need to be activated and sends the signal to both Power Cells. You could accomplish the same thing with the use of some relays, but that is going to still require you to do a lot of wiring at the relay or relay station. As of now I have three wires going to my light switch and only two wires to the floor mounted high beam switch. The starter relay was eliminated as well while the neutral safety gets wired to the Master Cell. When you think about it, it makes it extremely difficult for someone to "hot wire" your car without doing some time consuming bypassing of this system.
The one thing you do have to account for is some of the "luxury" items. There is not specific wire in the kit to provide power to things like the radio, heater, a/c compressor, and dome light. You do have to wire for those yourself. There are plenty of documents on their website to give you ideas and diagrams to get this done or you can call Isis Power to discuss options. You may have them do some custom programming to get what you need accomplished. In most cases, there are either open outputs and inputs in the system that can be used, or you can wire a relay to to be activated with the ECU/IGN/COIL output to provide power to those devices when the car is on.
I have yet to connect the inMOTION Motor controller. I intend to control my electric windows and power locks with it.
At the end of the day, if you are looking to add push button start, want to add starter and ignition kill functionality, and have need to replace your wiring harness, take a good look at this system. When you start to add those three things together you get close to the same pricing and much simpler to install. With the RF kit you get control over a lot of functions from your key fob as a bonus. Up to sixteen functions can be controlled with it.
When I finish getting everything installed (hopefully by the end of the week), sans the inMOTION cell, I will post some pictures and final thoughts. Once I get to the point to add the motor controller, I will update you all with that too.