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HomeElectrical
 Prototype
Typical 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 it provides Accessory, On and Start outputs with dual ON outputs where one shuts off certain parts of circuits while starting engine.

 

 


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.


 

 
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