After market touch screen fail

[Matt Todd]

I recently installed a alpine stereo with a capacitive touch screen and noticed the other day that the touch screen intermittently does not work. By not work I mean the controls of it, it still shows things, plays music and whatnot but you try to adjust the volume or change songs or anything like that and it just acts dead. I could be wrong but it seems to only happen in the morning, when I start my truck up in the afternoon after work everything works fine. Crutchfield has instructed me to take my multimeter and check to see if the stereo is getting a a full 12V when powered up and I will check that out tomorrow morning. I was wondering 1: if anyone’s experienced this before 2: if it’s a truck or stereo issue 3: where do I check the voltage, at the base of the power cable that connects to the unit itself?

 

[KC Cryptkeeper]

I recently installed a alpine stereo with a capacitive touch screen and noticed the other day that the touch screen intermittently does not work. By not work I mean the controls of it, it still shows things, plays music and whatnot but you try to adjust the volume or change songs or anything like that and it just acts dead. I could be wrong but it seems to only happen in the morning, when I start my truck up in the afternoon after work everything works fine. Crutchfield has instructed me to take my multimeter and check to see if the stereo is getting a a full 12V when powered up and I will check that out tomorrow morning. I was wondering 1: if anyone’s experienced this before 2: if it’s a truck or stereo issue 3: where do I check the voltage, at the base of the power cable that connects to the unit itself?

you might start the easy route and check at the battery first, if it is low then you know where the trouble is quickly. If your battery is losing power overnight then it would make sense.

 

[Matt Todd]

you might start the easy route and check at the battery first, if it is low then you know where the trouble is quickly. If your battery is losing power overnight then it would make sense.

Is that something would normally happen? Also, any idea what numbers I should be reading ideally from my battery?

 

[KC Cryptkeeper]

Is that something would normally happen? Also, any idea what numbers I should be reading ideally from my battery?

If your battery is more than say 3 years old yes it could be dropping to or just below 12v. A good new battery new usually reads a minimum of 12.8v before you start the truck.

 

[Matt Todd]

you might start the easy route and check at the battery first, if it is low then you know where the trouble is quickly. If your battery is losing power overnight then it would make sense.

Do we know if a low battery would cause a touch screen functions to not work only? I haven’t checked the bolts in the morning hours yet but just curious.

 

[KC Cryptkeeper]

Do we know if a low battery would cause a touch screen functions to not work only? I haven’t checked the bolts in the morning hours yet but just curious.

Well in your first post they said to look for a full 12v, so if the truck is at 11.8v in the morning, your truck would start but the radio might not get enough voltage. After driving and having the alternator charge the system back up you troubles go away until it sits long enough to get to a low voltage state. The radio is your case is more sensitive than the truck starting.

 

[Firetruck41]

The alternator should immediately be kicking out about 14v once the engine is running, so if the battery has enough power to start the truck, and your alternator is working, it probably isn't the battery that is causing issues with your stereo.

 

[KC Cryptkeeper]

The alternator should immediately be kicking out about 14v once the engine is running, so if the battery has enough power to start the truck, and your alternator is working, it probably isn't the battery that is causing issues with your stereo.

His issues are happening in the morning and they told him to check for a full 12v. I agree after starting the truck he should have 14v but the momentary starting voltage drop and current pull can be affecting the radio along with a potential problem of the voltage dropping over night.

 

[Matt Todd]

His issues are happening in the morning and they told him to check for a full 12v. I agree after starting the truck he should have 14v but the momentary starting voltage drop and current pull can be affecting the radio along with a potential problem of the voltage dropping over night.

So I just checked the battery this morning and it read12.56V

 

[Matt Todd]

Well in your first post they said to look for a full 12v, so if the truck is at 11.8v in the morning, your truck would start but the radio might not get enough voltage. After driving and having the alternator charge the system back up you troubles go away until it sits long enough to get to a low voltage state. The radio is your case is more sensitive than the truck starting.

Also let me say that when the issue happens in the morning it does not go away. Now so far I haven’t drove for hours first thing in the morning but during my 20 minute commute it does not remedy the touch screen issue

 

[Matt Todd]

I also am not sure how to check the voltage in relation to the head unit like they are asking. Since all the wires that are connecting to the unit insulated how should I go about doing that check?

 

[Firetruck41]

Also let me say that when the issue happens in the morning it does not go away. Now so far I haven’t drove for hours first thing in the morning but during my 20 minute commute it does not remedy the touch screen issue

The alternator should be putting out about 14v about 3 seconds after you start, it's not like you would have to wait for the battery to charge up to a certain point, the battery doesn't really matter, as long as the alternator is working at that point.

I also am not sure how to check the voltage in relation to the head unit like they are asking. Since all the wires that are connecting to the unit insulated how should I go about doing that check?

I would disconnect the wiring harness main connector from the back of the stereo and then use the multimeter red probe on the main 12v pin, and the black probe on the ground pin on the connector on the wiring harness.
You do not need to check for 12v while the stereo is plugged in, as long as you check the harness connector and you have 12v, you know that you are getting 12v to the stereo. If it's still not working, then there is something wrong with the stereo itself.

 

[Darth]

Perhaps the head unit itself is bad/faulty. Crutchfield has very good customer service. They should send you a new head unit if it's still within warranty period

 

[rotwiler]

Try a stylus to see if that works, Temps and even callous on fingers can interfere and may need to be warmer to work.

 

[Matt Todd]

So to all who are still following, here are my results from this weekends testing...

The headunit harness power and ground pin is reading 12.25V

The battery is reading 12.36V in the morning after a long sit

Battery after work approx 8 hr sit is 12.72

I’ll report the readings to crutchfield too and hopefully we can figure something out. My headunit is not even a year old so hopefully I can get a resolution from crutchfield.

 

[Firetruck41]

I should have mentioned, the numbers you really want, are with the engine running. As I assume that is the condition in which you are really having issues (not just sitting in your car in the morning with the car in accessory position with engine not running.) I would just do a quick test of voltage at battery while the engine is running. It seems like you aren't having any issue with voltage at the stereo vs battery. It is normal for it to be little different, so I wouldn't worry about removing the stereo again.
Sounds like it will be a head unit issue from what I am seeing so far...

 

[fastbike02]

what alpine head units I have dealt with usually have a boot up time after being left alone for x hours, they have a self check process they go through where you can't control anything for the first 5-10 seconds after the boot screen. That was on the older units as once I started using Kenwood I never looked back.

 

[KC Cryptkeeper]

So to all who are still following, here are my results from this weekends testing...

The headunit harness power and ground pin is reading 12.25V

The battery is reading 12.36V in the morning after a long sit

Battery after work approx 8 hr sit is 12.72

I’ll report the readings to crutchfield too and hopefully we can figure something out. My headunit is not even a year old so hopefully I can get a resolution from crutchfield.

Looking more like the radio all the way

 

[Matt Todd]

Well thanks to the lovely people at crutchfield, I’ll be getting a new exchange in the mail within the next couple days. I’ll tell ya, they have been some of the most pleasant people to deal with. Hopefully this will handle the issues and I can be done with this project.

 

[Darth]

That's good news. I've always been pleased with Crutchfield. Excellent customer service