ISIS – Intelligent Multiplex System???
 

After reading posts by L & H Kustoms, reboot04 and researching the ISIS website, I am debating whether or not to go with the ISIS system instead of a traditional wiring harness.

The pro’s of the system seem to be reduced time / labor for installation, reduction in number of wires, the flexibility to add additional circuits, reduced weight, and its programmable. There’s even a key FOB that will allow you to turn on the parking lights, headlights, instrument panel, 4- way flashers, cooling fan override, panic switch, ignition and enable / disable the car.

Cons - The initial price… but it could equal out if it takes less time to install.

Does anyone else have experience with the Multiplex system? Any thoughts?

Their website: http://www.isispower.com/index.html

Reboot04 website: http://www.onelapcamaro.com/build/isiswiring.html

Thanks for the help,

Mark

Good post. I was debating this same thing. Tyler @ ATS had good things to say about it. Maybe he will chime in...

I hope Tyle does chime in as I value is imput, here is mine, and I will say I don't have any experince with the product and I am just as interested as anybody.
But it looks to me that you will need the 3 cell unit @ 999.00 for a street car and many race cars as each unit has only 10 fused circuits. And for them to say that you can cut your wiring time in half, I don't see it as you still have to wire the same number of systems. Also the real time in wiring a car is layout, routing and terminating, anyone can just throw some wires into a car and make things work, the real trick is to run the wiring were it is servicable, functional and looks good, thats the time. FYI I'm not the wiring guys in the shop but I do work with them.

Kevin

Don't forget documentation. When doing something totally different like that, you have to produce your own as-built wiring schematics with termination diagrams. (Unless ISIS gives you generic schematics?)

I have looked into this as well. My concern is trouble shooting down the road. What happens if something in one of the "boxes" goes bad? With a standard system, you can trouble shoot with some wire and a light bulb from your tail light if needed. This system relies on technology only seen in OEM and industrial applications. You may not find a controls engineer in the middle of the power tour when your lights don't work. Just my thoughts. I would love to hear feedback from someone with actual experience as well.

I was also concerned about troubleshooting issues…but after some research I found that it does have an optional “diagnostic module” that helps you diagnose and troubleshoot the system. The module has a 4-line high intensity blue display. If it performs as advertised, it sure beats the old school way of troubleshooting

I'm going to try to set up a video interview with these guys at SEMA and get some of these questions answered... it's a very cool system and I'm intrigued as hell.

This is like the F1 car of wiring harnesses. Diagnostics are stupid simple as is the actual wiring of the vehicle. I'd recommend this to anyone who needs a chassis harness; it is the best, most advanced and simple install you will ever do when rewiring a vehicle.

Isis for life!

Tyler

That's very cool. It's not really clear, though. As I understand it, it replaces the body control wiring, but has nothing to do with engine management, correct?

Sounds interesting, I'll have to check it out at SEMA.

Looking at the details on their website, everything is pretty straight forward. But how do you integrate turn signal/brake lights/running light into this system?

Hey Guys,

Diagnostics are one of the strongest selling points of ISIS. Built into the MASTERCELL is the inSIGHT diagnostics module. This LCD allows the installer complete visibility to what is going on in the system. You can push a few buttons on the MASTERCELL and poll the critical functions from any POWERCELL attached to the system. You can get voltage at the POWERCELL, operating temperature of the board in the POWERCELL, and the status of each output node.

Troubleshooting of problems is very easy. Here's the path that you can follow:

First, everytime you close a switch, you get a written acknowledgement on the inSIGHT module. It tells you which switch closed and which POWERCELL and the output node that is supposed to react. Your switch is good and connected properly if you get the indication on the LCD screen. If you do not get any indication on the screen, you have a problem with your switch, the connection to the input harness or the connector on the MASTERCELL. If you get indication on the LCD, but it tells you that the target output node is incorrect, then your switch is connected to the wrong input wire.

Second, there is a "heartbeat" indicator on the MASTER & POWERCELL boxes. When these light blink, it confirms that each cell in the system is recognized and that they are communicating properly. If there is no heartbeat, it means that there is a problem with the CAN cable between the boxes or the connectors.

Third, each output node on the POWERCELL has a LED indicator and it does two things. First, this light is used to identify whether the output is on or off. You can flip the switch, confirm the switch closure on the inSIGHT module. If the light turns on when the switch is turned on, everything is working correctly. Second, the LED indicator on the output node also shows the status of the connection from the box to the load to ground. We continuously sink a few hundred microamps through each output node. Every load (lights, motors, solenoids) is connected to ground through some resistance. If the load is connected properly, the few hundred microamps leaks through the load to ground. If the load is not properly connected, those few hundred microamps have no place to go. The current passes through the LED and it glows, but at a lower brightness than when the output is on.

So here is the common diagnostic scenario. "My headlights have stopped working."

The first thing that I do is check the switch. I flip it and get the acknowledgement on the inSIGHT module. So I know that the switch is good and the connection to the MASTERCELL is good.

The second thing that I do is check for the heartbeat on the MASTERCELL and POWERCELLs. If I have a heartbeat, I know that the cells are communicating, the connectors and the cables are good.

The last thing that I do is check the LED indicator on the node on the POWERCELL. If the LED turns on, I know that the switch command is making it alway to the MOSFET that controls the output. If the LED is glows at half-power when the output is turned off, then I know that the the connection is broken somewhere between the output of the MOSFET and the ground connection. That means that a wire has broken, the fuse has opened or the filament in my headlight has burn out.

If you plan on being at SEMA...Check it out @ booth 11153.

I'm really interested in seeing this in person. I'll stop by your booth at SEMA.

Thanks for explaining how the system works.

Damn... where were you when I started wiring my car! Ah well, maybe on the next build.

Shiny Side Up!
Bill

Here’s a link to a video from V8TV covering the ISIS Intelligent Multiplex wiring system.

The video is a must see if you are planning on rewiring your car. I had troubles deciding what to go with - the Multiplex wiring system or a traditional wiring harness. After watching the video, I am now leaning towards the Multiplex wiring system!


https://lateral-g.net/forums/showthread.php4?t=17463