OBDIIc&c Hacks

                                    Last update:  4/10/2021 

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Normal OBDII scanners can not read all the special data points that is incorporated in the 1999 to 2006 Insights OBDII system. An insightcentral forum member Peter Perkins, has designed and sells an excellent OBDII scanner or the bare PC board specifically designed for the first generation Honda Insight. More information about this scanner can be found in the user manual.  

Please note that the OBDIIc&c free firmware is periodically updated so the manual may also have changes made over time. The insight central forum has two main links that discuss the OBDIIc&c .

1. The original thread, which is absolutely huge, can be found, here.
     This link opens with a description of the scanner. This link is now closed for new posts.

2.  This link  is the continuation of the original thread.
     New (free) firmware update HEX files etc will be presented there.

While building the OBDIIc&c gage and after using it for awhile I did a few hacks that improved the way I use my scanner. Perhaps they will help you too.  This page assumes you know how to solder and are familiar with tinkering with electronics.

To see an enlarged view of most pictures, click on the picture or right click and select "View Image".

Overall view of the hacks I've done

external view of OBDIIc&c

This view shows the extra push button and SPST dimmer switch I've added to my OBDIIc&c.  

The push button is a normally open switch. If your push switch has three leads use the common and "NO" (normally open) solder lugs.
inside view of hacks

Notice that I used two different style 5 pin connectors for the OBDII and the programming connectors. This keeps you from plugging either cable onto the wrong connector. The connectors are from junk computers & TV sets..

Sorry for the blurry picture. My Droid phone doesn't have much depth of field for closeup pictures. I'll try again with a real camera at a later time.
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Computer beeper
driver schematic

555 austable osc

Please note that capacitor C2 and the resistor values were chosen to match the resonant output frequency of the beeper I used. Those values may have to be adjusted slightly to match your beeper. Keep the duty cycle near 50%. Tune for maximum tone output from the beeper you plan on using.

The resistors can be 1/8 watt or 1/4 watt. I used carbon film for stability over time. The 0.01 mfd capacitor is a small ceramic cap. The oscillator is wired on a small 0.1" x 0.1" hole spacing "perf board".

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555 osc

This picture shows the assembled NE555 austable oscillator and where it is mounted. The lower lead of resistor R23 has been lifted from the solder pad. The white with the green stripe [WHT-GRN] wire (towards the right of center) titled [ENABLE] on the schematic is soldered to the free lead of R23. The WHT [BEEPER] wire is soldered to the R23 open pad.

The two wires with the same colors on the left side of the oscillator are the [5V] and [GND] leads of the oscillator. The [GND] wire is connected to the lower solder pad of the not connected C4. The WHT-GRN [5V] wire is connected to the Vcc (5 volt) lead of either R1 or R7 (your choice). The perf board is held onto the mother board with a dab of hot melt.

The red ellipse shows where the "push" switch wires are connected to pins #4 and #6. This will be described in another section (below).

Dimmer switch hack

closeup of resistors
This is a simple hack. Unsolder the lead of R20 closest to the case and move R20 to one side as shown in the picture. I used a 5.1K ohm resistor to bridge the lifted lead of R20 and the solder pad where the R20 lead was originally soldered.

Next install the two leads as shown above to each lead of the added resistor. Those leads go to a SPST switch that you will have to mount on your case somewhere.

I affect the added resistor reduces the applied voltage to the LED back lighting when it is not shorted by the Day/Dim switch. I used two wires from an ordinary computer ribbon cable for the all the hack wiring.

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Why do this hack?

Normally the (daytime) back lighting for the OBDIIc&c&c display defaults to 50% brightness. This may be fine for some areas but where I live the sun is very bright and I have to run the back lighting almost as bright as it can be set to. The setting is done in the configuration menu. The problem arises when you need to drive at night. At night the back lighting will be blinding if you have the OBDIIc&c mounted near your line of sight. Normally for night time driving you have to go back into the configuration menu and set the back lighting to be a lot dimmer. The next morning you have to repeat the process.

I decided to bite the bullet and not use the configuration menu route by just using an auxiliary switch to dim the back lighting by adding more resistance to R20.

The value of  the added resistor may not give proper night time back lighting brightness for you. If that's the case, try some other values around 5.1K ohms. Standard values are, 3.3K, 4.7K, 5.6K, 6.8K etc. Or you could use a miniature 10K potentiometer instead of the 5.1K resistor and set it to what you like for the night time (Dim) brightness.

How to set up the Dim back lighting.
Set the Day/Dim switch to Day and use the configuration menu to set the day time brightness. Then, if you are using a potentiometer instead of the 5.1K resistor, set the switch to Dim and adjust the pot for the night time brightness.

Auxiliary push button

switch connections

The ORG (orange) and YEL (yellow) wires go to the auxiliary "Push" switch in the picture to the right.

Capacitor C4 shown in this picture has the upper lead not connected to the mother board. While it's hard to see; the WHT wire [GND] is connected to the lower lead of C4 which is grounded. The WHT-GRN is connected to the lower leg of R1 which has the Vcc (5 volts) to power the NE555 oscillator.

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case no posts

This hack is the easiest one to do and is very helpful when using the "Push" function. The original push on the 5-way switch still works. I kept moving the original push in other directions which was very distracting while driving.

The momentary push switch on the left is ................ (wait for it) ......... the auxiliary "Push" switch. If your switch has three solder lugs; connect either the RED or YEL wire to the Common lug and the other wire to the normally open [NO] lug.

Connect either of the two wires from the added resistor to R20 to the center lug and the other wire to one of the outside lugs. The switch on the right is the dimmer SPST switch.

Where to drill the switch holes is left up to the student. Just make sure that the rear cover will still go on and not hit the switches. You can also see that the dimmer switch is above the I2C connector which I don't plan on using at this time. I can always move the switch later if I need to.

Additional 12 volt power filtering, 470 mfd, 25 volt capacitor
switch connections

The picture presented here shows the positive lead of the capacitor connected to solder pad #15 [12V]. This pad is next to the last one on the display SIP connector. The negative lead placement is shown on the picture to the right.

This hack may only be needed if you are powering the OBDIIc&c from the car's 12 volt switched bus instead of the car's OBDII connector. I was having problems with the OBDIIc&c booting with the faster firmware versions.

I noticed that as I turned the ignition key slowly to AUX and then to RUN that the OBDIIc&c display dimmed slightly as the 12 volt switched buss goes to 0 volts between the two ignition switch positions. After I installed the 470 mfd capacitor the display does not dim and the gage now boots OK after one retry.
case no posts

This picture shows the 470 mfd negative connection to the OBDIIc&c negative connection located on RV1. The wire is routed around and then soldered to the RV1 lug closest to the beeper end of the mother board.

It took awhile to bend, form and cut the capacitor leads but it is firmly held in place by the leads AND a small glob of hot melt between the capacitor and the mother board. Don't hot melt the capacitor to the case or you won't be able to remove the board if it has to go out the back of the case.

You can also see how the dimmer 5.1K resistor is mounted in this picture.

All the dual wiring used for these hacks are two wires from a computer ribbon cable.

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