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The MIMA plug in harness
|  | | | Help me find these connectors |
This next MIMA build of over 50 systems, is only going to work if I sub contract a great deal of the work to local businesses, and job shops.
I found it impossible to find an outside source for making the plug in pins,that were used on the last version of MIMA.
I really did not want to spend the hours and hours to build the wiring harness for 100 systems, I would have no time for anything else.
While I was prepared to do it, I did not want to make them myself.
Because of minimum order quantities, I had to buy the 104 pin 4 plug computer connector to get the male pins required to make the plug in adapter.
I had to remove the pins from the connector, a 10 minute a connector operation.
A big waste of time and a lot of difficult work.
I was able to buy the connectors in 160 quantity.
This gave me 160 of the most expensive and difficult to get parts of the connector set required to make MIMA a fully plug and play system.
I quickly found and bought all the connectors and pins required to make up 100 systems.
How it will work:
The plug in adapter will be a PC board with the computer 104 pin header on one side, and the four connectors with short harness wires on the other.
The ECM plug in adapter board will plug between the present harness connectors and the ECM. A small ribbon connector sub harness runs to the distribution card.
The distribution card also has:
A 10 conductor ribbon that runs to the AUX connector on the MIMA card.
A 20 pin ribbon that runs to the MIMA card.
A DB-25 female connector that will run to the rear IMA area and plug into the IMA plug in adapter.
Expansion port on distribution board.
This will be a 16 pin mate for the display/ I/O port, and a breadboard/socket area where a daughter board or hardwired circuit can be built.
This new port will allow full expansion of MIMA and this plug in harness for whatever future Insight modifications we can think of. PC interface, LCD touch screen, Master/slave port so MIMA can sit as a master, or slave board in a larger system.
The front to rear cable.
DB-25 cables are mass produced, available anywhere and are pretty reasonably priced.
The area that the MIMA harness has to pass through from rear to front is pretty tight right behind the seat. Most DB-25 cables are 1/2" or less, so they can thread through there just fine.
DB-25 cables are used for parallel printers and other computer interconnect use. The off the shelf shielded male to male pin to pin DB-25 cable is fished down into the rug on the passenger side of the shift console.
It comes out of the rug and into the e-brake console.
This carpet is too tight to get the DB-25 connector through without removing the passenger seat first.
From there it is fished up through a rectangular hole right at the bottom rear of the e-brake area, and up into the IMA box.
The DB-25 cable will plug right into the IMA(MCM) plug in adapter.
This adapter has the two temperature probes, the current sensor sub harness, and the fan control sub harnesses coming off of it.
The DB-25 can be left in the car and the ECM and IMA plug in adapters removed quickly.
Only problem is I can't find a source for the 2 pin and 3 pin connectors used on the current sensor and fan, so I may have to make something?
The connectors and the possible logo of the manufacturer is shown in the photo.
I was able to find the plug part of both the 2 and 3 pin connectors, and the recepticles with pigtails. They are used between the tail lights and the rear harness in late model Honda Civics.
Honda part numbers:
Two pin plug 04321-SH2-307 (pack of 5)
Three pin plug 04321-SM4-409 (pack of 5)
receptacles with pigtails 04320-SP0-B00 (pack of 10)
The plugs are half of the adapter, we still need the other half with pins to make the plug in adapter.
As you would expect,buying these connectors directly from Honda makes them very expensive, and they do not show a part number for the other half.
If you know the manufacturer, or know a better source for both sides of the connector, please contact me.
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The Plug in adapter boards are at the fabricator
|  | | | The final boards finally |
The final plug in harness boards ready for the fab shop.(8/19/08)
The board design is at Nashua Circuits, and I hope to see the finished product in next week or so.
Blue is top side, green is bottom side.
The ECM boards have pads to attach the FAS system.Three etch cuts at the fuel injector locations (oval silk screen)are required when FAS is attached. A single etch cut on the DC/DC enable line on the MCM board is required when FAS is used.The circles around a pad indicates that a pin wire must be attached. The thick circles indicate a large pin, thin is a small.
The ECM board has three extra conductors, E1,E2,E3, which can be used to bring any ECM signal to the distribution board. The Neutral,Clutch, Brake, and NEP(rpm) signals are included on the ribbon.
The MCM board has pads for seven spare conductors, M1 through M7, which can be used to bring MCM signals to the distribution board.
The distribution board ties everything together.
A breadboard area provides a place for expansion, both as a breadboard, or a place to mount a future interface board. The display 16 conductor ribbon connector can be plugged into the breadboard so other displays can be interfaced to that port. This expandable harness interface should provide all the future expansion that we will require to take the MIMA system to the next level, while making the system much simpler to install.
(Posted 7/26/2008 by mikey) |
Crimping the pins on the wires correctly
|  | | | Why the crimp is special |
Every connection going to the ECM and MCM will pass through my plug in boards. This requires that my connections are up to factory quality, which is why I must have the crimps applied to the pins with the correct factory applicators. Over crimping can cause stress cracks on the pin body, and possible failure, under crimping will cause wire pullout or intermittent connections.The small pins also require a special tall but narrow crimp in order to fit properly into the connector. No room for compromise here.
Good news. After contacting the AMP/TYCO field application engineer Rick Grawehr, things started to improve.
He dug right in, and checked his database as to harness job shops that had the correct tooling, and found RAM electronics in NJ, who has the proper factory automatic tools, and can crimp the terminals onto the 2" wire I require. They can turn it around in only a week, so the wire crimp issue is solved. The cost is pretty high when we consider that I need nearly 20K crimps, but it is in the ballpark that I have been getting for quotes, and tolerable. The pins are on the way to Ram electronics as of (8/19/08). Another piece of the puzzle has been solved.
(Posted 7/23/2008 by mikey) |
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