No announcement yet.

2003 Grand Cherokee 4x4 Expedition Vehicle - Worklog (dockable HP Laptop)

  • Filter
  • Time
  • Show
Clear All
new posts

  • 2003 Grand Cherokee 4x4 Expedition Vehicle - Worklog (dockable HP Laptop)

    STATUS AS OF 5/2012

    i started this over 2 years ago, and haven't made much progress
    the jeep has new axles, and many, many mods, and i even had to replace the engine at one point - so the carputer had taken a back seat.
    as of 5/2012 i'm actively working on the project again, here is how it sits today:

    screen and mini rf keyboard mounted on a ram mount with all my other electronics junk up front:

    Click image for larger version

Name:	P1110123.JPG
Views:	1
Size:	123.1 KB
ID:	2309037

    laptop is in custom cradle in back right corner pocket of jeep. docking station hidden behind trim panel, single cable connector from dock provides power and breaks out vga/usb/audio/etc:

    Click image for larger version

Name:	P1090633.JPG
Views:	1
Size:	72.5 KB
ID:	2309038

    manual on/off so far in the form of a momentary pushbutton connected to the quickdock power button for wake/hibernate. worked on an auto startup controller this week, will post details later:

    Click image for larger version

Name:	P1120028.JPG
Views:	1
Size:	114.7 KB
ID:	2309039

    no audio connections yet, still ironing out some bugs before the system is ready to replace the built in stereo. played some with centrafuse and road/ride runner last week to get an idea how everything could eventually function. also did my research on joycon and what's needed to get that working with the Jeep steering wheel controls. had taken the whole system out to troubleshoot some issues, in the next couple weeks should have the new carnetix power supply and put everything back together (so i can finally put my trim panels back on, i hate having the inside look all ghetto when i'm working on things!)


    Lurked here for a while, and now finally have aquired some of the hardware and am in the planning phases for my carputer for my 2003 Grand Cherokee 4x4 expedition rig.

    here's the rig and the current interior:

    if you would like to know more about the rig, i have a full build thread over here:

    up next, system needs, and info on hardware selection and mounting plans...
    Last edited by theksmith; 05-17-2012, 05:44 AM.

  • #2

    my vehicle serves 3 purposes:
    - daily driver
    - weekend 4x4 trail rig
    - expedition style camping rig

    so this isn't going to be your typical build, the things most people care about such as integrating into the dash or having a good audio/video system are the lowest on my priority list.

    reasons for wanting a carputer, in order of priority:

    1 - offroad navigation. handheld GPS have too small screens to use easily while driving offroad, the larger automotive GPS are too dumbed-down interface wise, and no pre packaged device can beat the flexibility of a true computer (like ability to run google earth and several topo mapping programs and a 3D routing app all at once and easily switch between them).

    2 - documents/info repository. a full factory service manual is nearly 2 inches thick, not practical to have along for the ride all the time. but with a computer i can have the PDF of the service manual, parts manual, and copy down many informative car websites such as to view offline). i will also be able to pull up instantly trip plans and routes, scans of endless bulky paper maps, other peoples or past trail photos to compare to current conditions, etc.

    3 - real-time vehicle/environment information display and logging. tying into OBD II and other custom sensors will provide great info on the health of the vehicle allowing less opportunity for problems to sneak up on you. breaking down 200 miles from anywhere in the middle of the desert sucks. having 100 gauges all over the dash sucks too. with a computer you can have endless virtual "gauges" and even store and graph trends.

    i also have this vision of eventually creating a custom application that will parse logs from tons of sensors that i want and then stamp all my photos from the trip with what the conditions where when the photo was taken, such as temperature, GPS coordinates, elevation, etc. (based on correlating the time photo was taken with the log info). I may also tie video cameras into the system and record video from the trip and then be able to play back the video later in a custom app that plays back the logs in parallel so you can see all the vehicle and environmental conditions as the video plays.

    4 - entertainment. currently i have the factory infinity soundsystem and it meets the needs of my non-discerning ears ok. i have an ipod integrated into the factory head unit and the factory steering wheel controls operate the radio and the ipod perfectly.

    i do eventually want a dvd player in the mix with rear headrest monitors for the kid. i'm yet undecided whether i will fully replace the head unit with the carputer for all my entertainment needs, or just purchase an aftermarket deck with ipod integration and dvd playing capabilities. getting a carputer to work with am/fm, steering wheel controls, video, multiple monitors, and most of all startup and shutdown quickly is not an overnight project. for me the simplicity of an aftermarket headunit for all the entertainment needs may usurp my desire for a single integrated system.


    • #3
      computer selection

      i decided to go with a laptop for now instead of a dedicated car pc. my main rational is cost, though there are some added benefits to using a laptop. i couldn't yet justify the expense of a dedicated machine and at the same time i was needing a new laptop. obviously, with a laptop sharing car and personal/business use duties, I won't always have a carputer running (yet another reason to keep my existing headunit for entertainment during phase 1).

      so i sold my old Dell laptop on ebay and used the $150 towards a refurbished HP TX2500Z 12" touchscreen laptop/tablet from ebay which cost me $580.

      a removable laptop also means that i can easily take the laptop out and under the jeep when using it to read the factory service manual PDF and working on the jeep. it also means that i can take the laptop over to the campfire and sit around and plan the next days route, enter GPS cooridinates, etc. or i can dump pics off my camera at the end of the day and share them around camp on the bigger screen. overall i could do all that with a seperate laptop and a dedicated car pc connected wirelessly, and i will do that probably one day, but for now this provides a very flexible lower cost solution.

      choosing the laptop

      my "must have" for the laptop were:

      - small size, under 13" so that i can find a home for it easily in the jeep
      - docking connector/station available that provides power and all ports with single connection to laptop
      - modern processor/ram/etc specs
      - affordable refurbished/used units available

      some of the Dell latitude series fit those requirements, but their docking station is huge, it's at lest 1/2 the volume that the laptop takes up, not conducive to in car placement.

      next i looked at the IBM x series. they are absolutely ideal in the fact that their mediabase dock is small and securely mounts to the laptop. you could screw down the base somewhere and easily dock and undock the laptop with no other real mounting needed. however, the older x series are really slow, the newest ones really expensive... so mainly i just couldn't afford this option. also, they only have the little eraser pointer thing instead of a touchpad and i hate that thing!

      so then there is the HP TX2000 and TX2500 series. it doesn't have a traditional physically connected dock, but rather a quickdock port replicator thing that also provides power to the laptop and does it all with one single cable (essential for ease of dock/undock... i didn't want to have to unlpug 5 things from the laptop everytime i needed to remove it). add to this the bonus of a touchscreen tablet style laptop and affordable ones all over ebay and you have the winner.

      integrating the laptop

      a car power adapter for the laptop cost me another $30. all in all i had everything i needed now for phase 0.5... what's the hell is that? well for a few weeks untill i get around to doing any more, i can at least run the laptop in the passenger seat in tablet mode with the car power adapter.

      the quickdock cost me $40. it provides usb, video out, audio in/out, power, and more importantly a on/off button. this way i will be able to hack into the quickdock to turn on and off the laptop with the car and not have to mod the laptop itself (which would also require another connector on the laptop).


      • #4
        screen selection

        when first thinking of this project, i briefly considered just mounting the entire laptop, in tablet mode, vertically on the dash and not using an external screen. however, it would be hard to mount securely there and still be easy to remove, and the laptop i ended up with was just to big to be practical in this configuration. i do think however this would be a perfect way to make use of a small tablet like the Asus T91 (the only reason i didn't go this route was that the little Asus wasn't enough machine for me for my non-carputer use).

        so i determined that an 8" screen was the max i could fit. i could do a 10" vertically if i really wanted to tear up the dash and get super custom, but 8" was much more realistic.

        i wanted a touchscreen so that i could easily interact with the sytem. i may eventually add some sort of other input devices. however, with the variety of programs i will be running and myriad of interface options they have, this project doesn't lend itself to a limited set of pre-programmed physical buttons.


        first off let me say i couldn't afford a trans-reflective although of course that's what we all want. with the shape of my interior and my fairly dark tint, i think a modern bright screen will be sufficient 90% of the time.

        at first it seemed that the latest and greatest 8" touch in my price range was the new Xenarc 800TSV and 805TSV. they had good brightness and contrast specs and used newer 5-wire resistive touch and led backlighting. one feature i was particularly interested in was the pre-set backlight brightness control with dedicated button (to easily adjust for night driving conditions).

        then a friend sent me a link to and i found that they have some bad-*** screens. the one that still fit my budget however was very similiar to the xenarc, the CTF845-5, but better in a few small ways: 100 more contrast ratio, 50 more cd/m2 brightness, a slightly cleaner and logo free case, and really kewl - an ambient light sensor to automatically adjust the backlight brightness. so i went with it!

        incidentally, i kinda preferred the look of the wide-screen displays, but was unsure if i could get the drivers for the laptop's built-in video to work with those resolutions or not and didn't take the time to really investigate it. the CTF845-t that i ended up with has the buttons on the side so the overall look of it is wide even though the screen is standard 4:3.


        • #5
          laptop mounting

          first thoughts were under the rear seat, with the laptop under the driver side and the quickdock under the passenger side mounted on top of the factory amp.

          this would provide easy access to remove the laptop, and when the seat is down it just happens to so nearly perfectly wedge the laptop in that not much more secure mounting would even be required.

          the main problem with this is cooling. i'm pretty sure that in order to provide airflow so the laptop wouldn't over heat, i would have to add some vents below the seat and maybe even a little fan here:

          overall that is kinda killing this first idea.

          my second idea is to use the cubby hole in the rear of the jeep. this will require longer cable runs than a mid-mount, but will still provide easy removal and there will be no cooling issue.

          overall this will require more fab work, some sort of padded cradle that fits within the cubby will be needed. i also have to see if there is room behind the plastic trim for the quickdock because it doesn't seem like it will fit with the laptop in the cubby hole and have room for padding the laptop.


          • #6
            screen mounting

            for phase 1, the screen will be mounted using a RAM Mount. ram has a standard 75mm vesa mount that will work with this screen, and the RAM base will be screwed into the dash.

            i already have a GPS and CB hanging out near the stereo, so it's not like i have this super clean interior. the gps will go away when the carputer gets put in, but will be replaced with a HAM radio mic, so there will still be a certain symmetry to the layout:

            phase 2 will most likely be to rip out the head unit and do a custom dash that will fit just the carputer screen, or the screen and a single din aftermarket head unit (if i decide to keep my entertainment and computer seperate).

            next step is to order the RAM base and mount and determine what arm length is needed to position it where i have it held in the picture.


            • #7
              carputer add on

              I like your idea for the removable computer as well as your idea of mounting your display. I'm doing something similar, but the carputer will be fixed and not removable. The monitor will be mounted on top of the dash over the radio in a custom pod. Right now, I'm testing placement of the mountor on a long trip before building the pod. The monitor is sitting on top of the dash using a gps base. I'm also testing all of the software on a laptop to work out the bugs.

              BTW, it is going into a 01 F250 Superduty pickup. Both my daily driver and tow vehicle for my camper trailer. I'll post photos in the next week.

              Good luck with your project.


              • #8
                remote turn-on for he quickdock

                last night i added a port for a plug for remote turn-on/off for the laptop via the quickdock.

                basicly you just need to get some sort of port from radioshack that has 2 conductors and is panel mount. i used a type M power adapter port/plug, but you could use a 1/8 mono or stereo audio plug, or a rca audio plug, or whatever they have.

                first, on the bottom, you have to remove the 4 outermost rubber feet and the label in the middle to get at 5 phillips screws:

                once those are out, you can use a medium size standard scew driver to start seperating the 2 case halves:

                once the top half is off, you'll end up with this:

                figure out where to put your port, i did mine just down from the SPDIF port. drill a hole (a unibit makes this easy to do without slipping in and ruining something on the inside. then test fit your port:

                you'll have to remove the circuit board in order to get to the terminals of the power switch to tie in to them. this takes removing several small silver phillips screws and then some carefull tugging towards the front and side as you remove the board. note that one screw is partially covered by a connector - you need to disconnect most of them anyway to get the board flipped over.

                once you have the board flipped, you can see the 2 pins from the existing power switch. solder your 2 wires to them (you're just putting your port in parallel with the switch). this is the hardest part because there just isn't much of anything to solder to, just 2 tiny pins.

                after you get done, you can put the board back in, and solder to your port and install it. you'll end up with something like this:

                re-assemble everything and now you've got a place to plug in your remote turn-on.

                to start with, i'll just run a remote switch up to the front. then when i get a chance, i'll wire up some sort of ignition controlled pulse switch circuit similar to this:


                • #9
                  ordered the base and vesa-75 RAM mounts tonight. after they get here i'll be able to determine exactly what length arm i need.



         was the best price including shipping that i could find, and then i found a coupon code for 5% off RAM products, so the total came out to $45. not cheap, but i know the RAM stuff is quality.


                  • #10
                    it's amazing how many pieces you have to remove sometimes just to get at the one you want... anyway i found out that there is going to be room to mount the quickdock vertically behind the rear corner plastic (right next to the cubby that i'm now pretty sure the laptop will be mounted in)...

                    see the hard lines in the carpet where the plastic sits, there's about an inch of space between the plastic and the metal, that should be perfect:


                    • #11
                      I have been wanting to do this to my grand cherokee for awhile. I want to have a pod for the screen tho. Might make a fiberglass pod that fits in the little flat unused spot on the top of the dash. I have a CD changer that I don't use, so I might put the carputer there. I thought about putting it under the drivers side rear seat too, but thought about the heat issue too.


                      • #12
                        yeah, i eventually want to make sort of "hood" out of metal or fiberglass that extends the black area (where the current radio, a/c, etc is) upwards above the dash a bit so everything would look integrated. then i would have room to either go with a 1 or 1.5 din radio and the 8" screen all in there... or if i go completely carputer and ditch radio, i could fit a 10" vertically in there, that could be pimp

                        i've decided to definitely run the computer in the cubby where the cd changer used to be, i don't want to have to worry about the heat issue under the rear seat, and there is some crap i keep under the rear seat already anyway that fits better there than in the cubby.


                        • #13
                          got my RAM mounts in the mail yesterday. went and bought some screws and washers today for the VESA mount.

                          it's funny how big and heavy-duty the mount is compared to the delicate little screen, but since it's going to be bouncing around off-road, i think the 1.5" ball based RAM mounts were the right way to go...


                          • #14
                            mounting the touchscreen

                            so got the touchscreen mounted and tested it out for secure-ness this past weekend in joshua tree national park.

                            so my dash has a 1/6" layer of vinyl, then nearly 1/2" of foam, then underneath all that is finally a solid 1/16" or so thick piece of plastic tray that actually holds everything together. this presented a couple challenges.

                            first, i chucked up a hole punch into a drill and used that to spin a nice clean hole through the vinyl and foam because i was worried a normal drill bit, or even a unibit, would tear the vinyl. this worked perfect for cutting down to the plastic. then i used a normal smaller drill bit to drill a hole just the size of my screw through the plastic base.

                            then i tried to just mount the ram mount with some nice black countersunk allen-head screws i got from ace, but that of course compressed the foam and pulled the ram mount and vinyl down into a depression that i thought would rip the vinyl in the sun over time.

                            the solution was to use some nylon spacers about 1/2" long around the screw so that the ram mount is pushing against those, and those are pushing against the plastic base of the dash. this way the ram mount sits nice and level with the rest of the dash but is still very secure.

                            here's the holes with the nylon spacers, ready to mount the ram mount:

                            the ram mount all nice and tight:

                            and finally how everything came out:


                            • #15
                              first tests with screen

                              i went ahead and just zip tied my GPS puck to the dash and ran the laptop in the passenger seat for the joshua tree trip so i could get some initial impressions of the setup... here's what i found

                              the good

                              - the screen is very secure even at high speed offroad, glad i went with the giant ram mount

                              - having a huge screen compared to a normal hand held gps is heaven!

                              the bad

                              - my gps and something else were having a conflict over IRQ or something and causing google earth to bluescreen within a few seconds of trying real-time sync, and causing ms mappoint to loose the gps signal within a few minutes every time... this should be a relative ez fix, i think it's the modem in the laptop and i can just disable that

                              - can't get the friggen cartft touchpanel drivers to work, so my touchpanel experience was crappy... i've tried the win 7 beta drivers and the win vista x64 drivers, but all i get is "no more controller"... nice error msg. i am going to email cartft for help.

                              - my fat finger isn't so precise with the touchscreen, especially bouncing around. i think i will definitely need to rig up a permanently mounted input device to go with the touchscreen. probably go with something like this mounted in the center armrest:

                              - the sunlight readability on my touchscreen is as good as i've seen anyone elses (that's not transreflective)... however, it still leaves something to be desired. i think i'll live with it for a year or so but definitely be saving up for a transreflective screen.

                              - ms mapoint works well for on-road nav, and if i have time to pre-cache the area i'm going to then google earth is a great asset for offroad, but i need a primary offroad nav app and i don't think i want to pay garmin, so i still need to find out more about overland navigator or if anyone knows of an alternative. something that could do realtime and show the free topo maps at would be ideal.