What trigger's car mode on Droid Razr Maxx HD?

maxc50167

New Member
Joined
Apr 30, 2013
Messages
3
Reaction score
0
I saw somewhere that Motorola's Vehicle Navigation Dock triggers car mode in the Droid Razr Maxx HD (upon connection to the dock's micro-USB).

What is special about the dock's micro-USB that automatically triggers car mode in the Droid Razr Maxx HD?
 

Yeti35

Active Member
Joined
Oct 1, 2010
Messages
158
Reaction score
46
Location
Utah, formally PA...:)
Current Phone Model
Galaxy S8+ w/ a Tech 21 case
It can be triggered just by using bluetooth if you have your phone paired with your car and use the Drive widget. I just recently started using it myself since I figured out what the widget does. I don't have a dock at all.
 
OP
M

maxc50167

New Member
Joined
Apr 30, 2013
Messages
3
Reaction score
0
I wish I could do that, but my car doesn't have bluetooth.

I just want to see what makes this dock so special.
 

kmf1

Diamond Member
Joined
Dec 16, 2012
Messages
6,095
Reaction score
8,448
Location
Northeast Iowa
Current Phone Model
Google Pixel 7 Pro Verizon
I believe that there is an extra pin contact that is sensed by the phone when placed on the car dock, which then activates the car mode. Some car mode apps are also activated by a magnet that is in the car dock. Also,as Yeti35 mentioned, there is a Drive widget that can be manually activated without blue tooth. You basically setup a manual Smart Action. It works well for me when I don't want to use a bluetooth headset.
 

FoxKat

Premium Member
Premium Member
Joined
Apr 2, 2010
Messages
14,651
Reaction score
4,703
Location
Pennsylvania
Current Phone Model
Droid Turbo 2 & Galaxy S7
I saw somewhere that Motorola's Vehicle Navigation Dock triggers car mode in the Droid Razr Maxx HD (upon connection to the dock's micro-USB).

What is special about the dock's micro-USB that automatically triggers car mode in the Droid Razr Maxx HD?

I believe that there is an extra pin contact that is sensed by the phone when placed on the car dock, which then activates the car mode. Some car mode apps are also activated by a magnet that is in the car dock. Also,as Yeti35 mentioned, there is a Drive widget that can be manually activated without blue tooth. You basically setup a manual Smart Action. It works well for me when I don't want to use a bluetooth headset.

It's true that earlier versions of the Droid (i.e. OGD and D2, and possibly D3), were triggered into Car Mode by a strategically placed Neodymium magnet in the face of the Motorola Vehicle Navigation Dock (or "Car Dock" and likewise into Desktop Mode with another Neodymium magnet), which lined up with tiny magnetic reed switches (or their solid state counterparts), in the phone's back, so that when the magnet is brought near, the contacts in the reed switch closed making an electrical connection and thereby triggering the desired mode.

However they have moved away from magnets in favor of an electronic "trigger" in the USB port for several reasons. First, it was the problem that many cases and belt pouches had magnetic closures and by simply sliding the phone into the pouch it would pass close enough to the magnet to trigger the undesired Car or Desktop mode and the phone would remain on in the case, thereby draining the battery unbeknownst to the owner. I am one who can attest to that since I used to carry my phone in a Blackberry case which it fit nicely, and I'd often take it out and see it was on in the case. For the longest time I thought it was a button being pushed by the case, but when I discovered the magnet trigger process, I would carefully avoid the magnet on the case when inserting the phone, and the problem went away.

Second, many people desired (and still do), to be able to place the phone into (or on) one of the two dock types without triggering the respective "mode". With magnets as triggers, that was mechanically impossible, so then apps were developed which circumvented that process, adding to the layers of background processes people had to run to make their phones act the way they wanted. This is less desirable since it only adds to the bloat that slows down the phones.

Fast-forward to the current models...

Now instead of the mechanical mechanism of magnets and reed switches, the manufacturers have opted for the use of varying levels of resistance applied across two terminals in the USB port. These specific tiny resistors are electrically conductive but limit the current that passes across these two terminals to a level that is electrically identifiable by the phone's internals, and so when the phone "sees" the 300 ohms for example across pins 2 and 3 for example, it "knows" that you are plugged into the "Car Dock", and when it "sees" 450 ohms, it "knows" you are in the "Desktop Dock". Now, the levels of resistance and pins are likely not the actual values I've used for purposes of explanation but the method and result are the same. You can open the internals of the docs and see the actual resistors there to "trigger" the desired mode.

In the case of the Car Dock on the Droid RAZR/MAXX (but NOT the M/HD/MAXX HD), you can now place the phone into the Dock, but NOT push down the plug, and it will remain in the normal operating mode and NOT trigger the "Dock" mode. In the case of the Desktop Dock, unfortunately that is not the case since the Dock and positioning of the ports are such that the phone is plugged into both the HDMI and USB ports simultaneously. I do not own an M/HD/MAXX HD, so I can't speak to the ability to use the Car or Desktop Docks without being forced into said modes, since from my recall (correct me if I'm wrong), the M/HD/MAXX HD have moved the USB and HDMI ports to the side and so inserting the phone into either Dock involves pressing the phone down onto the connections and thereby triggering the Dock mode.

Also, as mentioned the phone's "Modes" can be triggered by the car's Bluetooth system pairing with the phone upon starting. My Ford F-150 Platinum has MyTouch SYNC, so when I get into my car - even while my phone stays in my pocket, the phone syncs with the car, the car's stereo begins streaming music from my phone, and of course the full feature functionality of MyTouch SYNC are available to me, such as voice navigation and voice commands for phone calls, etc. For at least the Droid RAZR/MAXX, the phone isn't actually going into a particular "mode" so much as it is simply pairing with a Bluetooth appliance, but it "feels" like the two are now one. I often place the phone into the Motorola's Vehicle Navigation Dock in my car, but don't push down the slider that has the USB plug on it so I don't trigger Car Mode as I can't stand the limited operation in that mode and the large buttons are ugly. I suppose that means I'm not a viable candidate for the new Microsoft phone OS either!! LOL!
 
Last edited:
OP
M

maxc50167

New Member
Joined
Apr 30, 2013
Messages
3
Reaction score
0
Thank you for the responses!

It seems that the general consensus is that there are specific resistors between certain pins in the micro-USB of the dock that (upon connection to the phone) triggers car dock mode.

It looks like I may have to take apart one of their docks to see what this special wiring is. FYI triggering car dock mode in the Samsung Galaxy S3 is triggered by a micro-USB with a 619 ohms resistor between pins 4 & 5. However, it doesn't work on my Droid Razr Maxx HD, which means there must be different wiring.

If anyone is aware of this wiring, please let me know. Thank you again!
 

MrCatPC

Member
Joined
Feb 9, 2011
Messages
91
Reaction score
2
Location
South Dakota
So hypothetically, if I wanted to hack my Droid 4 Nav Dock (the new style not using magnets) into a hybrid HD Dock with USB/LineAudio dual-purpose cable as-is and add HDMI video output to say, other viewing screen(s) for example (HDMI video splitter/amp required I know), would it be possible to use the wiring and resistors for the Nav Dock paired with the HDMI/USB combo connector from a Moto HD Dock (or even HD Station with the 3-port USB hub** built-in) and attach that into the dock? Goal being Nav Dock USB identity with HDMI mirror mode on modified Nav Dock in the car...Yes the kids watch movies on my docked Droid, or they watch the Google Map Navigation or my wife playing games from passenger seat. Pretty far-fetched? I am ready to DIY this if I can get the right spare accessories for cheap. Will post (in a fresh thread) if I go exploring! :)K

** = USB hub might allow game controller(s) and/or storage drive(s) attachment into the docked Droid 4. Dreaming!

Thanks all, especially @FoxKat for the fantastic explanation at Post #5 above!
 

FoxKat

Premium Member
Premium Member
Joined
Apr 2, 2010
Messages
14,651
Reaction score
4,703
Location
Pennsylvania
Current Phone Model
Droid Turbo 2 & Galaxy S7
First, thanks for the complement! Well, it looks completely plausible. The key here is to know which two pins on the USB connector to join and with what level of resistance (Ohms resistance between the two pins), to trigger the dock mode. That's the easy part. The hard part is getting everything lined up nicely and secured such that the phone is simple to insert and remove, and so that the connectors aren't overly stressed.

We interrupt this program for an important message from FoxKat;

"And now it's time for A Cellular Soapbox Moment...

I am very disappointed that other manufacturers of phones don't spend the money in R&D, and take the care in creating custom docks as did Motorola. I thoroughly LOVED the docks I've had for ALL my past Motorola phones, and wouldn't trade for them with ANY other phone manufacturer. Now to the situation at hand, I have seen that Motorola has pulled away from manufacturing their own docks and have left that up to third party manufacturer Griffin who builds custom docks for them and sells them through the Motorola website. I'm here to tell you they are NOT the same quality, lack the real "custom" mount feel, and are more a "gripping" dock (spring-loaded), rather than the snap-fit or drop-in insert and lock types of the past.

View attachment 66719

My Droid RAZR MAXX (and the earlier RAZR), dock(s) was great. I now have a SGS4 and I've been relegated to the iBolt mount, an old-fashioned spring-loaded grip style mount, I have to plug the USB cord in separately and it's nearly impossible to insert it with just one had. Also, if I forget to pull the USB cord out BEFORE I remove the phone, I'll either yank the cord and break the mount, the socket in which the cord is connected, the socket on the phone, or if I'm REALLY lucky, I might have the phone unexpectedly fly out of my hand as I remove it from the mount only to have it go careening into the passenger compartment and onto the floor (which I'm sure you've figured out by now has happened to me - more than once). Also, I have a torn rotator cuff on the right shoulder and let me tell you, it's a bear getting my phone either into or out of that mount that I bought at Verizon's Phone Center Store.

This has been A Cellular Soapbox Moment from FoxKat".

We now return you to your regularly scheduled program.

So let's see what we can come up with that will blow the doors off anything that the other manufacturers can devise for your HD. By the way, does the HD have NFC? If so, then we should take a hint from the new Ultra and MAXX which are apparently triggered into Dock mode with the NFC rather than either magnetic or USB connections. At least it appears that way upon visual inspection.

View attachment 66718

Curious to see your idea on paper (or electronic facsimile thereof).
 

RemyL75

Member
Joined
Feb 13, 2010
Messages
311
Reaction score
18
Location
CHicago, IL
Docks made for specific phones with only trigger car mode mode for those phones (e.g.: The S3 car dock will not trigger car mode for any Motorola phones). I tested this theory out a while ago when i switched from Motorola RAZR to an S3. The docks would only work for the phones they were specifically made for (plus both docks had a custom-made holster for the dock so that made it difficult to put a different phone in the holster).

Also, there are docks that work with just one company's line of phones (iBolt has a dock like this for Samsung phones. I can attest that it works for the Note II and the S4). So, it's in the wiring, you just need to figure out which pins control what. Good luck.
 

kmf1

Diamond Member
Joined
Dec 16, 2012
Messages
6,095
Reaction score
8,448
Location
Northeast Iowa
Current Phone Model
Google Pixel 7 Pro Verizon
There is a built-in Smart Action that you can enable that doesn't require a special dock, or blue tooth. Not quite the same but it works well.

Sent from my DROID RAZR MAXX HD using Tapatalk 2.
 

Rognish

Active Member
Joined
Jul 25, 2010
Messages
238
Reaction score
79
Location
Ohio
Current Phone Model
Nexus 6
Twitter
rognish
I bought the combo car and desktop holder. I thought the holder did something to activate it. But I recently used the holder with a different power cord and it didn't activate the desktop mode. I'm leaning towards the power cord. Perhaps there is something in the car dock power adapter.
 

Sajo

Diamond Member
Joined
Jan 25, 2013
Messages
20,737
Reaction score
16,880
Location
Tennessee
Current Phone Model
Pixel 7 Pro
I bought the combo car and desktop holder. I thought the holder did something to activate it. But I recently used the holder with a different power cord and it didn't activate the desktop mode. I'm leaning towards the power cord. Perhaps there is something in the car dock power adapter.

The car dock has the special chip built in that launches vehicle mode. Did you get the flip stand dock? If so, did it come with the special power cord? Some of the stands on line don't come with the special cord and that's where the chip is that will launch desk or bedside mode.
 

Rognish

Active Member
Joined
Jul 25, 2010
Messages
238
Reaction score
79
Location
Ohio
Current Phone Model
Nexus 6
Twitter
rognish
Yes I got the flip stand and it came with a special power cord that you can't plug into the computer. It says it charges faster.
 
Last edited:
Top