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HomeElectrical
 Prototype
Typical (as seen to the right) conventional electrical wiring in modern cars is very complex and runs to almost every corner of the car and though manufacturers are starting to use smaller guage of wires its still can be of some weight.
Therefore wiring will be eliminated to use as view wires as possible and its its place a custom communication bus  with modules throughout the car be utilized to control various elements like lights and controls.  Benefit of it will be that all control lines will be practically eliminated and power carrying wiring will be reduced to just couple of feet to between modules and controlled devices. They will also can be reduced in guage as the drop on wire will not be as great due to the length of the power wire.  Benefit of it will be that overall electrical system will be much lighter due to lower count of cabling. Trouble shooting of electrical system will be greatly improved at same time.

Since all systems will be linked via single communication bus, sharing sensor and data collecting inputs can be shared between processing modules and processed for different operating condition. One example of it is the Gear Selector Indicator tough in this version it does not indicate communication bus connection.

Other example is the window drop circuit. In some circumstances it is required to drop door window my an inch so that when opening door it will not  interfere with door or window weather stripping then bring the window to a close when door is closed shut. This could also can be added to any OEM cars as add-on or with combination to alarm to either raise or drop the window.

 

Steering Column selection
Looking around for a short steering column that would fit in and clear pedals yet still have modern look was a bit of a chore as most North American sources had long columns before 1st U joint, same went for European counterparts. One choice was from Acura 04-06 TL which has a very short column, tilt and telescopic option and also the column controls are fairly good looking. Other option is from Honda Accord 04-07 which is basically as the TL but with bit different stock look.



Ignition Switch
It seems like the single simples thing is on the ignition  switch. Figure to the right shows wire color map and with only 5 wires it controls which provides:  Accessory I, Accessory II one which turns off during cranking and one that is on during cranking and a starter to crank the engine. Very straight forward like all other key switches.

 

 


Wiper & lights / turn signal control
The problem comes with the output from those switches. For some reason Honda decided to multiples the switch signals via microcontroller mounted in the wiper switch fed via CAN but into fuse box that they are calling it Multiplex Integrated Control Unit (MICU). To make things a bit worse they had decided to use Philips AU5790D or alternative TH8065 single wire CAN controller that is connected through 8 pin connector on the wiper switch where only 6 pins are used. It would had been so much easier if they had used differential (high - low) bus. The traditional way would had been to have individual wires from the switches going to according circuits however that would end up with around 14 wires. Not extremely large amount especially if you think that there is already an 8 pin connector used between the switch and MICU.

So came few questions:

1)
Should the column and the switches be replaced as putting alternative switches on the column be probably impossible to find switch with same mounts.

2)
Should the control board be replaced with custom one and more suitable interface ie normal CAN bus interface or LIN or K-bus

3)
Alternative option is to decode the bus protocol and make custom decoder with specific outputs or control module

4)
Other option is to use the Honda MICU fuse box and hopefully it will work as designed and not need any other modifications to it ie immobalizer. This probably is the least amount of work but will have to locate one box and try it out.

More on this in fuse boxes


Fuse Box - interior
There are a lot of fuse boxes that are ready made, pre-wired and labeled. Problem with them is that they are generally expensive $400 + for a basic configuration it does come with the basic turn and hazard flashers however if you are looking for relays then you are looking to add some extra $$ to the price tag if you like it all integrated in a single box or use external relays that will make the wiring look like cow pies
Since we are are using  Honda/Acura steering column and switch stock that comes with it so may as well use the  interior fuse block from that vintage of car.  After looking at the fuse box we had discovered advatages and disadvantages of it;
Pro:
 - lots of 33 small blade fuses
 - build in turn / hazard flasher
 - build in relays for fuel pump, etc...
 - wire are organized into buses/locations for interior of the car and are connected through connectors into the box

Con:
 - no direct control / connection from stock switches for headlights / turn, wiper etc..
 - internal control board needs to be reprogrammed or custom one to be made
 - not the smallest in size and rather bulky with all of the connectors

Despite of the short comings, sample was acquired and work had started to reverse engineer it.  Work on the process can be found on this link



Fuse Box - engine bay        
With all latest engines they are controlled by computers and have different circuit paths for various valves pumps etc... and need to be protected and switched on and off so an engine bay fuse box with relays is required. The problem is with exception of very few cars most are front engined and here is where the problem bigins. Their configuration includes circuits for things like front and  rear lights, horn and some even have circuits for other body controls. More link
 


Door control module
While looking at the interior fuse block, it had 2 dedicated connectors with 40 wires in the bundle going to the drivers (left) door though it does have the keyless entry module hence why so many. Passanger door (right) has considerably less and even less in the rear doors. To its defense it did came from a 4 door car, but never the less.. Not sure if the difference between the amount of wires and the door control module would be of great savings in weight but looking at more electronically controlled car desition was made to move forward with the control module and more information is on this link.


Brake intake splitter
Final version had not changed since prototype version and rather then of  repeating prototype can be found <here>. Though a version 2 of the light board was looked into which used RGB LED's so that different colors could be mixed. However it was never made


 

 
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