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iPod/AUX Integration with Stock Becker Stereo

25K views 87 replies 19 participants last post by  z168 
#1 ·
Just got done installing a GROM USB/AUX/iPod adapter on my stock Becker 1492. For those who might be looking at this as an option to integrate an iPod into their stock system, I'll offer my thoughts and observations:

The GROM unit was simple and straightforward to install. Remove the stock stereo, unplug the CD changer connector (if you have one) and plug in the supplied harness. Plug in the appropriate cable (more on that in a moment) and run the cable through the console and into the bottom box of the armrest.

No additional wires or connections are required. The GROM unit gets its power through the CD changer harness. Do note that you will lose the use of your CD changer with this unit.

Found plenty of room on the left side of the radio recess to stuff the GROM unit and cables. Radio went back in without a problem.

Power up the radio and using the provided instruction, press the radio buttons to select the input on the GROM unit and you're ready to go. The new input device will play through the radio when the CD selection is chosen.

The GROM unit has several different choices of inputs depending on how you order/configure it. The default setup uses a USB "thumb drive" (provided by the user) that you copy your music in .mp3 format in a particular way so that it can be "read" by the unit. Using your track selection buttons allows you to step forward and back through the .mp3 files. I tried this but found it to be a bit of a kludge and somewhat tedious to not only load the music on the thumb drive but also in playing it back. Crude but effective.

There are two cables that can be purchased with the unit or added separately. One is a standard 3.5mm stereo jack that allows the user to plug in any device that has a reasonable output. No controls through this method, of course, just playback of music from the device that you connect.

The other cable is for an iPod with the 30 pin dock connector. This is the way I went, as I wanted a direct connection to my iPod's line out as well as for it to be powered while in use (the iPod cable provides charging through the GROM unit, too.)

While plugged in to the GROM unit the iPod is powered and its output is not affected by the volume control as the line out signal is going to the GROM unit, not the speaker output.

I found that the GROM unit provided a very strong signal to the stock stereo, almost perfectly matched to the radio, so there is no noticeable difference in volume levels when moving between the two modes. High volume levels indicated no noise from the electrical system, so isolation appears to be very good.

The only negative I found is that the iPod is powered at all times. I can't imagine that this is a significant enough draw to cause battery depletion, but it is something to consider if you leave your iPod plugged in to the car for long periods of time while the car is not running. Another issue related to this is that due to the power remaining on at all times, the iPod does not turn off when you turn off the car. While this is more of a nuisance than a fault, the last iPod integration hardware I had would shut off when the car was shut off, and as a result the iPod would stop and start as the car did. Again, a nuisance at best, but something to be aware of if you are considering one of these devices.

You can shop around and find the GROM units for under $100. There is also a Bluetooth adapter available that allows you to pair Bluetooth devices to the GROM unit and use your phone and other Bluetooth devices through the stock stereo. It also includes a microphone for hands free operation of your phone. Going this route puts you in the range of $130 or more for the whole package, which is more than I was willing to spend as opposed to the $50 adder to a rebuilt Becker with an auxiliary input. Not to mention that I don't use my phone while I'm driving, so the Bluetooth option wasn't something that was desirable to me.

All in all the GROM unit is a great alternative to gutting your BOSE system and slapping some non-stock ghetto looking head unit in that would ruin the aesthetics of an already beautiful car, not to mention it's far less expensive as well.

If you have specific questions about the GROM unit, let me know.

Dan
 
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#38 ·
Chris,

I'm not familiar with your 1993 model, but if it does not have the factory BOSE system installed I'm not sure about compatibility with a modern head unit.

While the DIN connector will match up, I would want to be sure that the current amplification arrangement is compatible. I don't know how far back in the W140 the BOSE systems when, so that's why I'm unclear as to if it would work as a P&P in your car.

A couple of things you can check:

What model Becker do you have? If it's a 1492 or 1692 you'll be fine.

You can look on Becker's web site to see what aftermarket Blaupunkt units they sell for your model, as that will also be a giveaway as to compatibility with the Toronto.

If it is compatible, it is truly a plug and play arrangement. The DIN connectors plug right in to the Toronto along with your antenna lead, and that's pretty much it. You will have to install the metal sleeve for the head unit to slide in to, but that's pretty simple.

Dan
 
#39 ·
Follow up

Dan, I am out of luck. My car has the two piece radio and amp. The radio is the Becker Grand Prix 1432, doesn't appear to have anything comparable with the wiring. I think the 8 pin round connector causes more of the complexity with the chances of updates which led to Chris's thread about running extra wires to make another aftermarket radio work. For some reason I thought that when you stated direct plug in there was something I totally missed! Oh well, thanks anyway.

Chris
 
#40 ·
thanks

Dan and others, thanks for the info. I'm retrofitting a Becker 1492 into my '87 wagon, and have been considering my options for adding an aux input capability.
 
#41 ·
I ordered the Grom BT3 yesterday which will provide me with aux inputs and bluetooth capability for phonecalls and music. I plan on only using the bluetooth so I dont have to run any wires or modify anything in the interior.

Sorry for the noob question but I was wondering if you guys have tried or know of anyone who was able to hook up the stock microphone to the Grom unit.

Thanks!
 
#42 ·
I'm going to go out on a limb and say that it's probably impossible to connect the stock microphone to the Grom -- I actually think the mic was located on the phone unit itself, but I could be wrong about that. Either way, it would be a fairly involved process.

Do report back on how the bluetooth goes though, I'm very curious about that.
 
#43 ·
I think that the OE car mic for car phone should work w/ Grom

I already have installed Grom USB3 unit in W140 and have been enormously pleased with performance w/ Becker 1492/Bose system.

I buy hi-res digital files for home and downsample data t0 24bit/48kHz for Grom compatibility and play from USB sticks.

It requires some level of geekness to understand & deal with filesystem nomenclature & syntax to get proper track sequencing, but it's not hard.

Planning to integrate Grom USB/BT setup into R129 w/ same Becker 1492 headunit. This car had carphone option and mic has std 3mm/1/8in mini-conn (1-channel).

Most all of these mics are electret (condenser) mics which require some dc bias to work, but that's fairly forgiving.

AC audio signal is coupled thru series input capacitor. Very standard setup.

Bluetooth option means that iPod doesn't need to be wired to unit. This is going to be a major convenience for answering phone calls, etc.
 
#44 ·
daidnik,

If/when you wire the factory mic to the Grom BT, please post some pics or a link on how to modify the mic for connection. This would be amazing. I am a bit techy and willing to try the mod. If you can provide a walkthrough for this process I am sure we all would really appreciate it!

I get my Grom BT tomorrow, hoping it works out for my car but am unsure because I think my HU is the stock Alpine and I have the Bose speaker system. The website says it should work, lets see...
 
#45 ·
I've emailed the Grom Tech Support on this.

Chat session didn't work out as that person was not technically savvy. These condenser (electret) mics are forgiving and they are almost the universal type of mics being used.

I'm guessing that the DC bias is about 5-6VDC since that is midway between the DC rails of 0 & 12V.
 
#46 ·
Just installed the GROM BT3 and I'm really impressed! Sound quality is of course miles ahead of the Bluetooth dummy tape I had before. Bass is unusually high but I adjusted w the EQ. Also pleasantly surprised that the head unit's track and seek buttons work seamlessly with my iPhone 6 playing Spotify.
 
#48 ·
I emailed Grom Tech Support back & forth a couple of times today and finally confirmed that Grom BT setup uses electret (condenser) mic with std 3mm (1/8in) mini phone jack just like the one in the R129 from the old integrated car phone setup. Grom people said most integrated mics in car have wrong connectors and that was the basis of giving the "won't work" answer when I asked the question initially.

Now it looks like what I'm seeing on the '98 R129 SL500 should work with the Grom BT unit. The old car phone setup was located in the 'sunglasses pod' in the center. The mic mini phone plug is in there and I'm figuring to put the Grom BT unit n there and run the wire to the Grom box and locate that along side the Becker head-unit.

I'm really interested in any findings about the incoming call pre-empting the music and how the call answering 'hand-off' happens with the Grom BT unit using the head-unit & Bose amp system for audio.
 
#49 ·
I would think that the phone would pre-empt the music when a call came in the same way it does normally (i.e., if you were listening to your headphones and received a call). So you'd need to have the head unit input selected to CD and be listening to music from the phone. If you were just listening to the radio it wouldn't pre-empt anything, as the GROM unit can't automatically change the input on the head unit. At least, I would be extremely surprised (and impressed) if it could.
 
#50 ·
What's the user action to answer the call?

What's the user action to terminate the call?

Is the user interface for these actions going to be the phone?

It would also seem that there might be some need to adjust mic input gain to balance volume level with phone signal input to head-unit.
 
#52 ·
Also, I agree with Thom about the phone handling the muting of music and switching over to an incoming phone call.

I havent tested this system out yet, but the BT3 instructions state you can answer/reject/end calls with the track buttons on the HU. Apparently, if you have the iPod cable it will show the song info although I havent tested this and am not sure if that would happen on an MB HU.

Definitely excited about the possibility of being able to use the factory mic! I dont use the phone in the car much but this would be a great safety feature for sure.
 
#53 ·
If the Grom emulator is able to provide the Answer/Reject call function with track switch buttons, that would be totally sweet.

Keep us posted with your findings on this.

The BT 'no wires to phone' with music & calls etc. is really a no-brainer on these cars for the cost and ease of installation.
 
#61 ·
I need to add something so I can use the bluetooth/hands-free while driving, which one would you recommend a GROM or Blaupunkt Toronto BT?
Hands down, I would recommend the GROM unit. Having used it for a few days I am overall very happy with it. The unit automatically connects to my phone and starts playing music, all while keep the interior look completely stock. Even though I haven't hooked up the mic, the track controls do work to answer/decline phone calls.

The only issue I have had is that rarely the track button doesn't successfully change the song and occasionally makes the music app unresponsive briefly. Not sure if that is an issue with the unit or my phone but I am working with GROM to resolve this. Otherwise, its perfect.
 
#56 ·
The end or connector for the factory microphone can be found in the wiring that is bundled at the back of the eyeglasses case where the phone controller would otherwise go if the car was so equipped.

If you pull the false cover out of the back of the eyeglass storage area, there should be some cables bundled up in an opening at the right rear. Pull these out into the storage area so you can get to them and you'll find the plug for the microphone.

It's a small right angle plug that looks like a 3.5 mm plug, only it's smaller, like 1/8".

There's not a lot of slack, but I was able to get it down to the radio opening with some work. This was in my R129 (SL500) but the setup is the same for the W140. In my case I couldn't get it to reach the head unit, so I bought a short male to female cable from Monoprice for a few bucks to make it reach to the head unit.

Dan
 
#62 ·
Couple questions:

When you brought the wire down to the HU, what did you hook it up to? The GROM or a Parrot?

Also, how do you pull out the dash phone? I've searched online and cant find detailed walkthrough or video. I'd love to try to get that factory mic to the GROM somehow, or worst case put the GROM mic in the sunglasses cubby if I can make it fit in there.
 
#57 ·
Yes

If it's like the R129, which I'm pretty sure it will be, there is enough slack to run the wire into the 'sunglasses/phone' pod location.

What's this about 'false cover' in the enclosure?

I would think that the box would have to be taken out to get to the plug in the wiring. I think this also requires removing the lock cylinder on the right.
 
#58 ·
I think I see now how the back panel inside the enclosure is a separate piece from the rest of the enclosure (unlike the glove compartment).

Looks like removal of 2 screws in the back & lever/pull back panel wall out of the sunglasses enclosure.

Is this correct?
 
#59 ·
Correct.

You may have to use a hook or some other means to pull the harnesses out of the recess, but they are there and ready to be pulled into the space.

No need to remove the box itself unless you want easier access to the cable.

Dan
 
#60 ·
I always leave mine ON & it always remembers track, etc when car is OFF. I think the Grom is always getting power as you can turn ON head-unit without putting key in and also CD changer would usually have power at all times for cassette eject.

I'm playing from USB stick. Only time it gets confused is when I swap USB stick while off. Then it seems to go to CD (Folder) 01, track 01 when powered ON with surprise swap of USB stick.

I did also see bigger Grom confusion when dealer put scan tool on car to program new key & my other key and delete all other keys. When I got car back, Grom wouldn't engage with head-unit at all. I had to pull radio & disconnect Grom to cycle power on it, then it came back as usual.

Another computing mystery.
 
#63 ·
I still stand by the Yatour system with bluetooth connectivity which totals ~$150 full setup and keeps stock radio. I've hooked it up on both my cars with no issues, plug and play. All controls work if you're using a USB, and if you're using bluetooth, it overrides the USB (digital cd changer). My cars look stock, and functions like the newer cars. It comes with a microphone that you have to place somewhere, it's a tiny dime sized diameter microphone that I squeezed in under the iginition switch between the console and footwell. I can provide pictures or a video of how it functions.
 
#65 · (Edited)
#67 ·
I just made the video for ya. Here you go.

https://www.youtube.com/watch?v=8-_F4X1U5Oo

Here's the links to where I bought it from

Yatour CD digital changer:
USB Adapter MP3 CD Wechsler Mercedes W140 W202 W210 C E | eBay

Bluetooth Module:
Yatour Bluetooth Modul FÜR USB Adapter YT M06 M07 M05 Freisprecheinrichtung BTM | eBay

Correction to video: The package was a total of $115 USD with shipping.

Is that a W220 head rest instead of the original W140 head rests?
 
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