R230 Head Unit Replacement - OEM Aerial Adaptor/Connection?

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WolfieS

Member
Joined
Oct 1, 2013
Messages
40
Location
Westbury, Wiltshire
Car
2005 SL350
Hi.
I am/have replaced the Command Head Unit in my 2005 SL350 and am installing an Alpine X800D-U connected to a JL HD900/5 Amplifier to run the OEM BOSE Speakers. All working so far EXCEPT I am not receiving an FM Signal at the head unit (the aerial connection from the head unit and up to the Audio Gateway location is fine).
I had thought that it would be a very simple case of connecting the aerial lead from the Alpine into an Aerial Adaptor that connects to the OEM Aerial Connector at the Audio Gateway, however, this does not work - I am not receiving an FM signal at the disconnected Audio Gateway.
Several of you on this Forum must have fitted replacement head units into an R230 in the past ... where and how did you connect to the OEM Aerial? It is obviously more complicated than just unplugging the 'black' aerial connector at the Audio Gateway and plugging in an adaptor - any clues or solutions please?
Thanks and regards
Wolfgang Souter
Westbury, Wiltshire, UK
2005 SL350 (R230) formerly with Command Face-Lift Head Unit.
 
SL has powered antenna system. You need to feed it power when HU is on.

I can't remember whether its phantom fed or discrete power though. HU has a power output for powering it. If its phantom fed you need a phantom feed inserter.

Richard
 
SL has powered antenna system. You need to feed it power when HU is on.

I can't remember whether its phantom fed or discrete power though. HU has a power output for powering it. If its phantom fed you need a phantom feed inserter.

Richard
I was beginning to suspect that I needed to power the antenna ... any ideas about where and which wire I need to piggy-back onto to feed power?
 
I was beginning to suspect that I needed to power the antenna ... any ideas about where and which wire I need to piggy-back onto to feed power?

If its phantom fed, its not a piggy back. The power runs up the coax to the antenna amp and you need a power inserter.

MY2009 onward is definitely phantom fed. I just can't remember what it was before. If it was discrete before, it is likely to be fed from the AGW that you removed, so look at the wiring on that. It probably was discrete wire though.

R
 
Its come back to me:)

Discrete power feed from the AGW. Small blue cable (or perhaps pair of them) on the 4 way connector main power feed to the AGW.

I assume you have extended the AGW power feed up to the new head unit, and have run a nice chunky cable for the amp back to the battery in the boot.
 
Its come back to me:)

Discrete power feed from the AGW. Small blue cable (or perhaps pair of them) on the 4 way connector main power feed to the AGW.

I assume you have extended the AGW power feed up to the new head unit, and have run a nice chunky cable for the amp back to the battery in the boot.
Hello Richard, can you clarify what you mean by 'discrete power feed from the AGW'?... do you mean that I need to connect/provide ACC power (12v Ign or Remote Turn-on from Head Unit) into the pair of blue wires entering the AGW at the 4-way connector? I note that the pair of blue wires both enter into the same plug terminal, so only one connection to presumably make.

I had not run a discrete power lead to the AGW from the head unit as I had not realised that I still needed it - in fact, I originally removed the AGW completely until I encountered the problem with poor/no FM reception and then refitted it; however, the lack of FM reception remained (hence this thread).

Regarding power to feed the JL Amp ... 'yes', a nice chunky cable, but run through the trunking under the pax seat and connected to the large terminal block up behind the subwoofer in the passenger footwell. Took a bit of patience to pull such a large diameter cable through the trunking without taking the seat out, but managed it after about two-dozen attempts and a bit of lube.

Thanks and pleased if you could confirm whether I now only need to feed power (ACC or Remote Turn-on) into the blue wires connecting into the AGW to thereby reactivate my power aerial to receive an FM signal?

Regards
Wolfgang Souter
Westbury, Wiltshire, UK
 
Hi

a) You have a 900Watt amplifier. Your feed needs to go to the battery. You can't connect such a large amp to a random fat power-feed as that power-feed is designed to run the car, and not the car plus another 60 amps peak. (I have said 60 amps, which is less than 900 W @ 12v because thats what the HD900/5 spec says)

Ensure you use the correct size fuse (60Amp in this case according to JL) (to protect the cable and the amplifier) placed very close to the battery (so damage to the cable anywhere causes the fuse to blow not the cable to catch fire). I've seen too many installed by the amplifier not by the power source.

b) Yes, the head unit's electric antenna output / remote-amp-turnon is used to both turn on the amplifier (via it's remote turn on input) and to turn on the antenna system, so connect it to those 2 blue wires that were fed from the AGW
Some amps (maybe the JL does) will detect audio signal and turn on - i've preferred to use a wire where possible.

Richard
 
Thanks Richard ... I will connect to the blue wires at the AGW (will now have to be next week) and then update this post.
Regards
Wolfgang
 
Hi and thanks ... connected the Alpine Remote Turn-On to the Blue wire(s) going to the Audio Gateway - actually removed the AGW from the vehicle - and now have a decent FM signal.

Reception issue resolved and many thanks Richard for your time plus advice.

My next project will be to fit a Rear Camera, but where best to integrate the camera? Not much space above the numberplate as my SL350 has the additional button for Keyless Entry/Go. I have seen a camera that replaces one of the numberplate lights but it is 0.5mm smaller and I have yet to figure out how to remove a numberplate light as a complete unit.

Anyway, thanks again and kind regards

Wolfgang
2005 SL350, Westbury, Wiltshire
 
If you have no use for your, now removed AGW I would be interested in taking it off your hands.
mine is deaf & I am looking for a replacement.
My R230 is early 2007, but I think the AGW part numbers are similar.

If yours has a part number ending in 40 89 (possibly 28 89) and you are happy to let it go then please email me.

crippo2 (email is [email protected])
 

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