[MTCB Android Head Units Q&A] ajayel:
reviewing the KLD eonon 5151

Updated August 2015

Updated September 2015

Updated June 2016

Updated June 2017

It's been a of couple months years since installing this Android double din radio into a 2008 Mazda 3. I like it (most of the time!). If you are technically inclined and have the time to fool around with the device and don't expect perfection you will like it too. I've put a heap of time into getting it setup however without the XDA community I would have quit on this thing a while back.

So here's a write up of what we found, what we learnt and what we want it to do differently.

This review does not cover software mods, rooting Android or overriding factory functions. Any work that you carry out described here or otherwise is entirely at your own risk.

June 2017 - The biggest improvement which has made this unit from average to great is disabling the Google Play Services and Play Store. Did this by disabling the services under the apps menu. I think there would be side effects with some google apps but that's ok as i've switched to Waze rather than GMaps. The head unit now starts faster is much more responsive and the buttons respond quickly even if the DVR is recording.

June 2016 - Malaysk custom rom for Android 5.1.1 is very good. Remember to donate to him via PayPal. 5.1.1 seems more stable and this ROM is clean, tidy and fast.

September 2015 - I tried Malaysk's custom ROM dated 19.08.2015. Very cool and recommended because it looks and works great. It's not only a visual update but many important features are built right into the software such as screen dimming, alternate music player support and so on. Remember to donate to him if you use his custom ROMs and yes I did :)

The decision to order via eonon.com was made easier when the company advertised a free reversing camera. The item was delivered from Hong Kong by DHL on the date promised. All items were well packaged and initial impressions were of a nicely made radio. And yep the reversing camera promised was in the box. The second impression was the impressive and overwhelming number of cables gadgets and adapters, again each in in neat plastic bags. Once we took a good look around the installation manual was noticeable by it's non existence although a printed one page wiring diagram was supplied and the company offers a You Tube video. Whilst some models have PDF manuals on the website the keyword GA5151 turn ups few search results.

Basic Installation

I didn't understand the You Tube video on the company's product page for this device. It started out with joining certain cables together that my radio didn't have which threw me off the scent. Please disconnect your vehicles battery whilst working on the radio.

To remove the stock radio simply unclip the shiny plastic wedge that runs above the glove box and over the centre console. Be sure to unclip the centre first as there is a hook on the door side of the wedge you do not want to break. Now remove the two screws that hold in the radio and pull out the old radio gently to release the sprung clips that hold the bottom of the radio in place. If you are a stereo thief don't read this :mad:

Unclip the connectors at the back of the old radio then remove the old radio completely. Now with the old and new units side by side remove the black sprung clips from the bottom of the new radio and replace them with the white sprung clips from the old radio. I used a small screw driver to carefully prise the clips off the radio chassis. You should not have to undo any of the screws. The reason is that the supplied clips didn't fit solidly into my car and the bottom of the radio hung out at least a centimetre with the supplied clips. If this triggers early warning bells you are correct and this is one of the many small things that make owning the unit, well let's say a stimulating challenge.

OK now unscrew the four screws holding in your factory LCD message display from the old radio and use the brackets supplied to fix it onto the new radio. We are now ready to plug in the new radio to see if it works. Note there are now many more cables and the canbus box to fit in to the same space in your car so keep the mass of cables as high as possible whilst sliding the new radio back into position. Eventually I used strong double sided tape to hold the canbus box to the top of the unit just behind the LCD display.

September 2015 - so someone did try to steal my stereo but did not succeed. I now need to know how to setup a passcode at startup so that e-mails, photos, documents etc.. are a little safer.

Connected and powered the unit took around thirty seconds to boot up whilst showing the Mazda factory logo and then straight into the Android screen as advertised on the product page. The screen looked nice and the FM radio worked immediately.

It is very cool at this stage, the old factory radio never had a calculator, USB, Wi-Fi or SD card slots. Installating Angry Birds ensured this really was Android and no problems - the game and sound ran smoothly through the car speakers.

You'll notice the time displayed on the Mazda LCD display is different to the time on your new Android radio. The manufacturers have included an app to fix this. Open ControlSettings and hold the clock button to simulate the buttons on your old radio to set the time. Anyways it was good not to have to throw out the Mazda LCD screen as many other after market radios require.

Sound Quality

Is fine, use the build in graphic equalizer to adjust the tone if necessary. Initial impressions are that the volume doesn't go quite as loud as the factory radio however at that end of the volume range either system would be shaking the speakers. Remember to use an uptodate MCU such as 2.55 with audio enhancments via http://huifei.fs-fileserver.de/ and first read up on this forum how to identify and update MCU.

Touch Screen Response and Brightness

The screen is bright enough to use on a sunny day. At night it is very bright and despite the illumination cable detecting when the headlights are on the screen is barely noticeable and still way too bright. However it's saving grace is the mute button on the front fascia panel. Pressing mute once will mute audio. Holding the mute button will mute video ie. turn off the screen leaving the audio playing which is a fine feature.

The touch screen sensitivity of this unit is very good but as with any touch screen is is slippery and dangerous to use it whilst driving.

Wi-Fi, 3G, 4G and LTE network connectivity

Devices like these shine when the internet is immediately available and as such network connectivity at home and whilst driving is worthwhile. I've played around with a number of connections and found the built in Wi-Fi is weak. Whilst you can connect a USB Wi-Fi dongle I didn't try that but did connect a Huawei USB modem containing a SIM card. The radio is supplied with cables labelled 3G/Wi-Fi and the online manual for Android 4.2 systems recommends which dongles can be used. I removed the glove box completely which only requires a few screws to be removed and wired these two USB cables from the back of the radio to the back of the glove box as there is a small removable panel perfect for cutting two notches into to bring the cables through.

I purchased a Huawei E3131S USB modem from my mobile provider which came supplied with a prepaid data package that can be be topped up. The E3131S did work right out of the box and the 3G symbol appeared on the screen and amazingly we could browse the net from anyplace that had a cellular data signal. I don't think I get full speed data what with the modem being in the glove box but it worked quite well. Until realising that with some apps internet connectivity just didn't work. Browser worked fine but the Google Play Store app and Pandora just refused to do anything but fail. I also borrowed a Huawei E5373 mobile Wi-Fi unit that happily broadcasts strong Wi-Fi when plugged into the cars cigarette lighter socket. Over Wi-Fi all of the apps can access the internet. Some users on the forum have reported that the 3G sub system on this radio is not stable.

With the connectivity in place navigation apps can get live traffic updates and gives a base model vehicle more features than it's top of the line equivalent. Your cellphone can now be neatly tucked away and it's battery will not get used up because the car radio is handling navigation, internet and GPS. The Android radio can provide a Wi-Fi hotspot but as the 3G modem does that anyway we've not needed to figure that out. The other experiment is to connect an external antenna to the modem to boost data speed although this is not a problem as with the modem in the glove box we can Skype, listen to streaming radio and watch You Tube, Netflix and so on - whilst parked up of course!

The problems I still have are sub system or driver level related perhaps no custom ROM can fix issues such as the 3G dongle working only with certain apps or Google Voice search continuously crashing. This is fixed by using correct APN settings. The google Voice crash thing seems more stable with Android 5.1.1.

GPS

There are plenty of navigation apps on the Google Play store. I tried Sygic, Google Maps, Nokia Here and a few others. Nokia Here maps is our current goto navigation app because it's free, works offline and provides traffic data whilst online.

To install the supplied GPS receiver I used strong tape to fix it under the top part of the dashboard above the central air vents. The panel removes easily by removing the screws above the radio fixing screws and there is plenty of space to find a place for the GPS receiver. It offers a good signal updated approximately every second so feels quite responsive when apps use location.

For a simple security system we installed the open source Traccar software which transmits the vehicle location back to a server every minute.

Reversing Camera AKA Backup Camera

I really didn't want to install the reversing camera myself. I hadn't done something like this before and didn't want to mess up the vehicle as cables had to be run from the head unit all the way to the back of the car. After contacting two local auto audio shops who had a long wait time I pencilled in a weekend to try the process.

The first thing was to figure where to place the camera and I went for fixing it just above the rear license plate. The license plate is fixed to a soft plastic panel which now has two tiny bolts holding the camera in where it is almost invisible. I ran the camera cables into the trunk via a large rubber grommet in the trunk that takes power to the license plate illumination bulbs. I'm not sure if it was the best way but used an electric drill with a large bit to work a new hole into the grommet that the camera cables just made it through so a nice tight fit.

The camera has a socket for the long signal cable and short leads to connect to the reverse light power and ground at the back of the car. Find your reverse light cable in the wiring loom and connect the short leads to this cable and to a good ground point. On my vehicle the best place for this was just behind the rear seats on the left hand side of the car - I say left as if you are sitting inside the car facing forward. The panel around the seat belt feed can be removed and there was a cable in the loom that became live with the gear shift set to reverse. This needs to be identified from the wiring diagram for your vehicle and checked out very carefully at your own risk using a bulb tester or multi meter. I then made, soldered and protected the joins for the camera cable up here but had to extend out the supplied short leads with some old speaker wire to reach.

The long signal cable was then run just underneath the carpet on the left hand side of the vehicle and then under the glove box and to the back of the radio. To get the cable to the back of the radio the small panel in the footwell pops out and a straightened coathanger can fish the cable up to the required area. Connect the backup video signal cable to the supplied adapter at the back of the radio and connect the cable labelled reverse to the red wire attached to the long signal cable.

No one was more surprised than I was when this system worked. When the engine is running place the gear shift into reverse even if the radio has not fully booted up and the hardware will switch to the reversing camera image. The picture isn't great but it is a great improvement over having no visibility of children, pets or objects that could be right behind the car. It's worth wiping the camera lense once in a while during wet weather before getting into the vehicle.

Radio

The FM Radio is fine it works but is not quite as sensitive as the factory radio. For example scanning through the frequencies using the next station arrows on the tuner often misses the required station which then must be hunted down using the fine tuning buttons. The frequency adjust button on the bottom right hand side of the fascia allows us to adjust fine tuning but not search for the next station which is kind of useless.

For some reason the radio drops stored station memory after software updates which shouldn't be required.

Bluetooth and Microphone Madness

For some reason the Bluetooth name of my unit occasionally resets to Car Kit or some such. This is a good reason not to change the bluetooth name on the radio.

The biggest disappointment of owning this radio came when trying out Bluetooth calls. We tried pairing to different phones and using different external microphones. All of the phone calls were aborted due to the terrible sound quality from the Eonon. It just didn't work. Contacting the suppliers e-mail support returned a quick response but simply advised to speak within 1m of the microphone - which is hard not to in this vehicle.

This is where this forum once again became invaluable. It seems that both the internal and external microphone are run unshielded and connected together inside the radio to the bluetooth module and then somehow also connected to the Android audio chips. I don't understand all of this except the call quality was useless and one of the reasons I bought the radio was for the bluetooth functionality.

The forum posts advised the capacitor that links both inputs should be removed and a new external microphone socket connected into the unit using shielded audio cable. The challenge for me was that the photos posted to the forum didn't look at all like the radio I was working on. Until I found this post and decided to open up the radio and have a go at fixing the problem.

I tried to open the unit by removing all screws at the back of the casing. Don't do this! I also tried opening the front by removing the wrong screws and ended up messing up the front panel SD card slots.

Purchase a mono 3.5mm microphone extension cable and cut it so about 50cm is left from the socket. To open the case remove two screws from each side of the front of the unit. The front will then fold down be careful not to stress the ribbon connectors inside. Now you can identify the bluetooth module which is a vertical card just inside the left hand side of the case. Next remove the side panel by removing the tiny screws at the front left, front side, rear left and top left of the case. I did not remove the main PCB but worked on the new connection from the top. I followed the notes in the post described above although slightly differently which is described on here. I put a knot in the cable just inside the radio case so if the cable got pulled it would not wreck the new connection. A few spots from the hot glue gun keep the cable in position around the case.

Now the internal and external microphones are separated only the Bluetooth module will use the new microphone. A few test telephone calls shown the difference in quality being amazing. Also the Android microphone seemed a lot clearer on Skype test calls and Android voice recognition. A couple months on bluetooth calls are still good. If we were told before purchasing the radio a soldering iron and PCB modifications would be required to get basic functions working would people still purchase this item?

September 2015 - iPhone pairs automatically with the 5151 over Bluetooth 90% of the time. Sometimes the connection needs to be manually specified on the iPhone before bluetooth pairing works. I guess is probably an iPhone issue more than anything else.

Music Player

The default music player works well. Like most of the default software it's kind of simple but you can get used to it. You can run Poweramp which is one of the best but the Mazda LCD screen then shows 'other' rather than track info and switching sources for example to the radio can leave two songs playing at the same time if the radio app is not exited first. There are apps available to override default settings and this page will be updated once they have been tried.

Add music files to any of the USB or SD cards available and the tracks are available to music player.

Video Player

Easy to use once video files are placed on storage similar to the music files described above. It's kind of fun to have a movie playing with the screen muted so just hearing the dialogue through the speakers whilst driving.

DVD

Haven't tried this yet. 3 months in - still didn't bother :)

Airplay and Screen Mirroring

Yes this is possible and works by installing the AirPin Pro app. The sound quality of music via AirPlay is definitely better than music streamed to the radio via bluetooth.

Voice Control

So one of the cool things would be to have Google Now recognise voice commands to open apps, maps, check e-mails, open music and so on in a hands free fashion. It works intermittently for me and I receive numerous error messages such as Google Voice could not open the microphone or more commonly seen is a generic error message right after the Google Voice recognition dots show up on the screen. This is real annoying as it could be one of the best features of such a car stereo system. I've given up on this feature now as the error happens with every ROM installed and every combination of launcher, clearing caches, personal data, factory resets and so on. Usually after Google Play updates the Google app it will work for a few days and then fall-back into the error message every time voice search is activated. This happens when voice search is triggered by tapping the microphone button and also when Hey Google is configured. My feeling is that somehow the low level configuration of the firmware or a driver is causing a problem and it may not be fixable by anyone other than the supplier.

Update June 2016 - this is much better with the 5.1.1. update.

B]Upgrades[/B]

My unit shipped with a dual core processor. We upgraded to a quad core module from XDA forum expert typos. The seller is very knowledgeable, the unit arrived quickly, was easy to install and works perfectly. Boot up time has been improved and the unit feels a lot faster to use.

Wish List

The firmware for these units need to be open source. The manufactures would then sell many more units because there is already a great community of people sharing knowledge and providing improvements, patches and support to other users. These radios are held back by firmware that prevents many simple things from working out of the box. For example;

Night time screen brightness settings - this is can be addressed by installing a custom ROM

Ability to change default apps for music, video etc.. - this is can be addressed by installing a custom ROM

The screen doesn't need to turn on every time the volume is changed -

Support for Android 5 see above

The microphone circuits must be redesigned and assembled correctly in the factory

Would be cool if the radio didn't begin power down whilst the engine is starting although I guess this happens with most systems. Update this is fixed by adding a capacitor and diode solution

Improve the power circuits because our car battery goes flat if we don't use the car for three days. This didn't happen before installing the radio. It seems that may have been caused by an OBD2 dongle