drex Posted March 17, 2009 Report Share Posted March 17, 2009 Hi, I've been searching and could not find anything to answer the problem I have had with my touch screen. About 2 days ago, my touch screen started going crazy (it would not respond and after leaving it alone for a few minutes it'll execute the buttons which I did not push many times and very fast). Since that incident, the touch screen only works randomly. It still works but very unpredictable and seldom (very unstable). I can still hear/listen the sound/music from AM, FM radio, SD card and USB but I can not execute any of the soft buttons. This unit was purchased and installed 4 months ago by me with the hardware bypass instruction posted on the F-series section of the forum. I am pretty sure I grounded the unit properly since it worked for 4 months?! Everything worked fine for the first 4 months (except during extreme cold days the unit will turn on and resets itself until the car warms up inside) until now. All wires are soldered and double wrapped in heat shink tubes. The unit is running firmware 2.0 and bt hw330. I've reset the unit many many times, removed my SD and/or USB key. I don't use an SD card over 8GB or USB over 2GB. No cd in the HU. What else am I doing wrong? I call Pioneer and they told me the unit is not properly grounded but I asked them if it's not properly ground it then how is it possible that I was able to use it for 4 months without any issue? The response was the same, that it was not properly grounded. Quote Link to post Share on other sites
mhtn Posted March 17, 2009 Report Share Posted March 17, 2009 You may have a cold solder point somewhere. It may not be obvious when you first installed the HU but it is now after awhile (after hitting some potholes ?). I would check the ground wire 1 more time. Quote Link to post Share on other sites
WilliamG Posted March 17, 2009 Report Share Posted March 17, 2009 I had this same problem with my F700BT. I did not do the ground or parking brake mod. I ended up exchanging the unit for a new one. Quote Link to post Share on other sites
drex Posted March 18, 2009 Author Report Share Posted March 18, 2009 You may have a cold solder point somewhere. It may not be obvious when you first installed the HU but it is now after awhile (after hitting some potholes ?). I would check the ground wire 1 more time. I will check all soldered connection one more time and the ground wire to make sure ( I ground the ground wire to the HU bracket, is this advisable?). I'm quite careful when it comes to soldering the wires to make sure it doesn't come loose and made sure it's properly insulated to avoid shorting. Will update on whether if it's a cold solder point and/or bad grounding or just simply a bad unit. I hope it's not a defective unit as Firmware 2.0 has really grown on me and I'm really starting to like this HU and I can't wait for Firmware 3.0 if that'll happen. Anybody else with this experience please post. I understand touch screen technology is still relatively new but I hope this is not a wide spread problem. Quote Link to post Share on other sites
mhtn Posted March 18, 2009 Report Share Posted March 18, 2009 I ground the ground wire to the HU bracket, is this advisable? I would make sure that the ground wire has good contact with the metal frame part of the car. The HU bracket is not not welded to the metal frame and this could be the problem. I grounded my F700bt to the vehicle's ground wire for the factory HU and it worked great. Quote Link to post Share on other sites
drex Posted March 19, 2009 Author Report Share Posted March 19, 2009 I ground the ground wire to the HU bracket, is this advisable? I would make sure that the ground wire has good contact with the metal frame part of the car. The HU bracket is not not welded to the metal frame and this could be the problem. I grounded my F700bt to the vehicle's ground wire for the factory HU and it worked great. Took the unit apart tonight and checked all solder connections and shrink wrap: OK. Checked hardware bypass again: the light green wire from the Pioneer black "power harness" was connected to the yellow/black stripe "mute" wire from the Pioneer RCA harness and both light green wire and the yellow/black wires were grounded to the black ground wire to the adapter harness that I bought separately. The yellow/black mute pin was moved to the correct position between 2 black pins. Since I used a vehicle specific harness adapter to install the F700bt, after the wires were all soldered together, I used the factory ground wire and grounded it to the radio metal plate (the OEM HU's bracket). I assume this is where the problem is? This setup worked flawlessly for 4 months with no issue except for when I used the Navigation feature, a legal disclaimer message comes up. To use the navi all I have to do is hit the "OK" soft button, I assume that's normal. No problems until 3 days ago when the touch screen goes unresponsive and unstable on me. mhtn, your suggest would be to abandon the OEM ground wire setup, splice and tap a ground wire to the chassis of the vehicle? Thanks for your response. Quote Link to post Share on other sites
mhtn Posted March 19, 2009 Report Share Posted March 19, 2009 I had almost the same set-up as you did except that I did not cut the vehicle's ground wire and ground it to the OEM HU bracket because my vehicle's ground wire was already grounded. My factory HU was grounded through the vehicle's harness, so I used the same grounding set-up for the avic. From what you described, your avic used the same ground wire as your factory radio did, so the set-up you had should have worked fine. Before sending the avic to Pioneer for check-up, I would move the ground lead from the OEM HU's bracket to where the ground lead had been for the original factory HU. Make sure that the ground lead has direct contact with the vehicle's metal frame. Quote Link to post Share on other sites
drex Posted March 19, 2009 Author Report Share Posted March 19, 2009 I should have been more specific with my details. The black ground wire from the Pioneer's black harness was connected/soldered with the light green (parking brake) and yellow/black (mute) wire and to the after market harness and then connected to my stock OEM harness. I did not tap into the black ground wire and grounded somewhere else because I assumed that the stock harness was already properly grounded. I do have a black wire which I assume it's the ground coming from the OEM HU's harness that attaches to the HU's bracket. I re-used the OEM HU bracket to mount the F700BT and it fits perfectly except for 2 screws (the 2 screws does not affect how secure the F700BT mounts). When I plugged all the harnesses together, I simply plugged/reconnect the "extra"?! ground to the right side of my HU bracket. As mentioned previously, this setup worked flawlessly for 4 months and I'm no ICE/computer installation expert but I do try to follow instructions very carefully and I am now suspecting this unit has a defective touch screen. It must be the hot/cold extreme that killing the rams on these units...and the Kenwood I am sure is no exception, unless they have a proprietary approach to protect the rams or IC's or CPU... The hardware bypass instruction on this forum was pretty much idiot proof IMHO, so I am sure I did not screw that up. Will update you people on the outcome. Quote Link to post Share on other sites
vrdubbin_360 Posted August 19, 2021 Report Share Posted August 19, 2021 I have an avic-f700bt i got a smokin deal on because it needed an update and the PO didn't have the resources needed to do it....I'm aware its an ancient HU, I updated it and it worked quite well so I installed it in my car and had the same issue of an unresponsive screen my issue ended up being a mounting screw that was too long I replaced it with a shorter one and now everything works flawlessly Quote Link to post Share on other sites
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.