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TomPierce
08-09-2009, 10:49 AM
This DIY is how to make a short extension for a DashHawk cable with an on/off switch.

The DashHawk unit continues to read the CAN network in your car even though the vehicle is turned off. This contributes to running down your battery if the vehicle is stored for more than a few weeks without a trickle charger.

This cable extension will enable you to turn off your DashHawk so that it does not run down your battery, and without having to remove the unit from it's mount. This extension plugs into the existing cable and the DashHawk without having to modify either.

The additional advantage is that you can attach the USB cable and download the logs (once the power is turned off) without having to remove the unit from the car.

Parts needed

1 - Molex connector housing PN 43025-0800
http://forum.grrrr8.net/attachment.php?attachmentid=2855&stc=1&d=1249839531
In the picture above, the #1 pin is the leftmost in the bottom row.

4 - Terminals/pins PN 43030-0002 http://forum.grrrr8.net/attachment.php?attachmentid=2856&stc=1&d=1249839531

1 - Molex connector housing PN 43020-0801
http://forum.grrrr8.net/attachment.php?attachmentid=2854&stc=1&d=1249839531
In the picture above, the #1 pin is the leftmost in the top row. (note where it is in relation to the latch clip on the bottom)

4 - Terminals/pins PN 43031-0009
http://forum.grrrr8.net/attachment.php?attachmentid=2857&stc=1&d=1249839531

I got twice as many as I needed - they are easy to screw up and they only cost a few cents a piece.

1 - small switch (rocker or pushbutton ... SPST on/off)

1 - length of shielded 4 conductor (or more) wire as long as needed
(Note: I used individual wires instead of shielded cable because my extension was so short - beyond about 4 or so inches you should probably use shielded cable to avoid noise)

These parts are readily available from www.digikey.com, www.mouserelectronics.com, www.alliedelec.com, etc.

The 0800 connector uses the 0002 pins, and the 0801 connector uses the 0009 pins. If you forget - look at your existing cable or the DashHawk unit :)

Getting your bearings

Look at the end of your existing DashHawk cable. With the latch at the top the pins are numbered like this:

latch
5 6 7 8
1 2 3 4

Look at your DashHawk unit. With the latch at the top the pins are numbered like this:

latch
8 7 6 5
4 3 2 1

On most cables, only the number 1 (power) and 7, 8, and 4 pins are actually used. We will be making up a 'pass thru" cable where pin 1 is connected to pin 1 through a switch, pin 4 to pin 4, pin 7 to pin 7 and pin 8 to pin 8 directly without a switch.

Decide how long to make the unswitched wires - a few inches is usually enough to reach from the existing cable to the DashHawk unit. Make up 3 wires of the same length with a 0002 pin on one end and a 0009 pin on the other. Crimping tightly is good, soldering is better.

Decide where you are going to mount the power switch. I mounted the switch on the back of the DashHawk unit itself with some double sided tape so that only the switch handle shows from the front. Make up a wire with a switch in the middle long enough to reach from the end of the existing cable to the switch and back to the DashHawk - put a 0002 pin on one end and a 0009 pin on the other.

NOW COMES THE CRITICAL PART

Connect the wires and pins into the connectors.

Make sure that pin #1 goes to pin #1 on each connector.

Note that the 0800 connector and the 0002 pins are shown in the correct orientation in the pictures above. Slide them in until they latch - you may need to use a small screwdriver to push them in. Refer to your existing cable or DashHawk for proper alignment.

Make sure that pin #1 goes to pin #1 on each connector.

Do pin #1 first, and then plug the connectors into each other. Make sure that there is a completed 'circle' for pin #1. Then do the remaining wires.

You're almost done. Mount the on/off switch, plug the extension in, and enjoy.

Now if you have a dead battery, it's not the DashHawks fault. :)

On the other hand, a trickle charger might be easier.

08G8V8
08-09-2009, 11:18 AM
Great DIY post! Very much appreciated.

R.Penguin
08-09-2009, 12:33 PM
WOW! I'm thinkin' that will be a lot easier than clipping the cable with side-cutters and then re-splicing every time I leave town.

No shit, that's a good post. :p

Also, I'm thinkin' this might allow the 'On Star' satellite to read the car info too. :woohoo:

GRRRR8
08-09-2009, 04:41 PM
Excellent info!!

08G8V8
08-09-2009, 05:43 PM
Can you post a pic of how you have your DashHawk mounted with your switch?

Thanks

Mlozano
08-09-2009, 06:21 PM
Nice job, could use some pics of the final product.

R.Penguin
08-14-2009, 04:18 PM
If I don't drive my car in 7 days, I start convulsing & shit myself. :rofl:

Panzer Leader
08-14-2009, 05:54 PM
There once was a Penquin from Seattle
Who at times while conversing would babble.
No problem said he, I am in good company,
their all shit kicking rabble.

Now some times it seems,
His car was in his dreams,
And we all know what that means,
Because Penquins leave tracks from their dreams.

rez0nance
10-08-2009, 10:53 AM
Reviving an old thread here... Is this confirmed to allow Onstar to read your car when you switch it off?

TomPierce
10-08-2009, 10:56 AM
Not confirmed, but I would assume that it would. Without power it should not interfere with OnStar.

rez0nance
10-08-2009, 11:27 AM
Excellent, thanks for the quick response. One more question, as I just ordered most of the parts: Which rocker switch part number did you go with? There is some serious option overload when it comes to SPST on/off switches, and I was wondering if there was some specific one that works best in this application.

The shielded cable should be easy enough to find.

TomPierce
10-08-2009, 11:57 AM
I used one I had in my junk drawer - it was probably a small Radio Shack toggle switch left over from some other project.

And for those who asked for an installed picture - the switch is visible at the top right of the DashHawk.

http://forum.grrrr8.net/attachment.php?attachmentid=3778&stc=1&d=1255031710

rez0nance
10-08-2009, 12:50 PM
Ah, you used a flip switch. That's definitely a great idea for switch placement.

I'm going to try to mount my Dashhawk above my rearview mirror using a Blendmount. I already have my V1 in the Blendmount under the mirror, and the DH mount just screws to the top of it. Clearance (with the headliner) is the only issue I have to check on, but given that our mirrors are double jointed it should be doable.

The DH Blendmount came with with an extension cord to run up as well, so I won't need very much cable at all, just enough to hook the switch up to.

Thanks a LOT for all the info Tom, this was definitely a top notch DIY thread. :theman: