B200 radio reception issue

[peten2005]

Hi there, this is my first post so be gentle lol.

As of recently, the radio in my car hasn't been able to catch any stations, with the exception of 1 or 2 FM stations depending on my location. AM does not work at all however.

I've looked all over the internet to find solutions to this problem with no luck. I initially thought it could be a problem with the antenna amp so I immediately searched for it. In another post, someone had stated that the antenna amp in a B Class W245 can be found in the OS storage compartment in the boot, behind the lining. Nothing was there. I've also checked some of the fuses but that didn't seem to be the problem.

I'm new to this sort of stuff so any help I can get would be much appreciated.

 

[Diesel Benz]

Is it a W245? Which head unit? Radio antenna amplifier (one or two) is located at the top of the rear-end door (tailgate), behind the inner panelling.

 

[peten2005]

Is it a W245? Which head unit? Radio antenna amplifier (one or two) is located at the top of the rear-end door (tailgate), behind the inner panelling.

Yep it’s a 2010 B200, w245. Not sure what head unit but it looks just like the image attached to this reply. I have also checked for the amp behind the panelling of the tailgate, no luck unfortunately. Although I did manage to break a pin Perhaps you can send me a pic of what exactly the amp should look like? Not sure what it should look like exactly, I’ve seen many different aerial amps when searching online. Thanks.

 

[Diesel Benz]

Yep it’s a 2010 B200, w245. Not sure what head unit but it looks just like the image attached to this reply. I have also checked for the amp behind the panelling of the tailgate, no luck unfortunately. Although I did manage to break a pin Perhaps you can send me a pic of what exactly the amp should look like? Not sure what it should look like exactly, I’ve seen many different aerial amps when searching online. Thanks.

It would be best to search for parts with the vehicle VIN. This is an example photo from WIS if it helps:

 

[peten2005]

It would be best to search for parts with the vehicle VIN. This is an example photo from WIS if it helps:

Ohh boy do I feel stupid right now lol. This is the area I checked. Thanks for the diagram, makes a lot more sense now. One more question, how can I test the amp to ensure that the amp is the problem?

 

[Diesel Benz]

Ohh boy do I feel stupid right now lol. This is the area I checked. Thanks for the diagram, makes a lot more sense now. One more question, how can I test the amp to ensure that the amp is the problem?

I'm afraid you need the diagnosis tool for proper testing but you could check the amplifier supply voltage with a MM. I'm not familiar with the W245 and don't know if poor reception is typically caused by a failed antenna amplifier, poor contact to the rear window antenna wiring or supply voltage or control voltage from the head unit.

 

[peten2005]

I'm afraid you need the diagnosis tool for proper testing but you could check the amplifier supply voltage with a MM. I'm not familiar with the W245 and don't know if poor reception is typically caused by a failed antenna amplifier, poor contact to the rear window antenna wiring or supply voltage or control voltage from the head unit.

Mhm ok I’ll see what I can do. Thank you so much for your help, have had this issue for a while now. It’s good to know that I’m one step closer to having it fixed. Will get back to you once I can take a look at the amp. It’s near impossible to work on the car in -20°C temperatures

 

[peten2005]

I'm afraid you need the diagnosis tool for proper testing but you could check the amplifier supply voltage with a MM. I'm not familiar with the W245 and don't know if poor reception is typically caused by a failed antenna amplifier, poor contact to the rear window antenna wiring or supply voltage or control voltage from the head unit.

So it most definitely is not at the back… after breaking some more pins I soon realized there was nothing actually there, aside for some cabling. I have a feeling the amp is at the front (behind the vent above the radio unit as shown in the picture below). As little sense it makes to me to have the amp at the front of the vehicle, could this be it? Mercedes-Benz A/B-Class W169 W245 Antenna Amplifier Antenna Soft A1698200475 | eBay. Let me know what you think. Here’s the VIN btw, WDDFH3DB6AJ501816

 

[Diesel Benz]

OK, option code 510 head unit, model year 2009 or later makes it all different.

You must have the roof antenna, the one that is usually a shark fin type but this time no fin but a "proper" whip antenna.

The wiring diagram still talks about the left rear door antenna but parts diagram says it is for cars with a serial number higher than 158503, not applicable for your car.

A whip antenna does not need any amplifier but there may be one integrated to the roof antenna unit. The internal implementation is not described.

 

[peten2005]

OK, option code 510 head unit, model year 2009 or later makes it all different.

You must have the roof antenna, the one that is usually a shark fin type but this time no fin but a "proper" whip antenna.

The wiring diagram still talks about the left rear door antenna but parts diagram says it is for cars with a serial number higher than 158503, not applicable for your car.

A whip antenna does not need any amplifier but there may be one integrated to the roof antenna unit. The internal implementation is not described.

It is a 2010 and I do have the whip style antenna. Didn’t think that there could not be an amplifier… So then I guess the issue lays somewhere in the wiring maybe? Also, which website do you use to check for information based using the VIN and where did you find the diagram?

 

[Diesel Benz]

It is a 2010 and I do have the whip style antenna. Didn’t think that there could not be an amplifier… So then I guess the issue lays somewhere in the wiring maybe? Also, which website do you use to check for information based using the VIN and where did you find the diagram?

XENTRY Portal for us in Europe. Startekinfo in the US, not sure about Canada.

Need subscription.

You already told the MY, that was when you provided the VIN. It is the 800 "option code" in your data card.

If you have FM reception issues, shouldn't you try a third party antenna attached to the head unit to try it? The roof antenna units fail surprisingly often on many MB models (don't know if 245 is prone to have that issue).

 

[peten2005]

XENTRY Portal for us in Europe. Startekinfo in the US, not sure about Canada.

Need subscription.

You already told the MY, that was when you provided the VIN. It is the 800 "option code" in your data card.

If you have FM reception issues, shouldn't you try a third party antenna attached to the head unit to try it? The roof antenna units fail surprisingly often on many MB models (don't know if 245 is prone to have that issue).

I’ll have to see if I can subscribe to it temporarily. How much does it cost in Europe monthly? Also when I search for option code 800, I see AEJ 09/1, what is exactly? I can try to get a third party antenna however my main worry is how I’d manage to route the new cable in the event that it is damaged. Also, not sure if it matters too much but I have absolutely no AM reception, with little FM reception.

 

[Grandy]

Hi. I have exactly the same problem. My Arial amplifier is also not in the rear boot cupboard. We have tried replacing the radio but no joy. I am replacing my Arial base on the roof this weekend and will let you know how I get on. I’ve had to return one already brought, as it had 3 wires but mine only has one brown wire and after some searches managed to get the correct matching one.

 

[peten2005]

Hi. I have exactly the same problem. My Arial amplifier is also not in the rear boot cupboard. We have tried replacing the radio but no joy. I am replacing my Arial base on the roof this weekend and will let you know how I get on. I’ve had to return one already brought, as it had 3 wires but mine only has one brown wire and after some searches managed to get the correct matching one.

Hi there, I’ve actually fixed this problem and the radio is now running perfectly. Turns out the amplifier is actually situated inside the base of the antenna (the little housing underneath the antenna whip). Water somehow made its way into the base and corroded part of the PCB. A good cleaning with some soldering seemed to have fixed the problem for me. (view attached image). To remove the base, I popped the interior head lamp cover (at the rear of the car) off and gained access to a nut that was holding the base in place. To gain access to the wires, I pulled the headliner from the rear of the car and immediately saw the connection. There was one brown wire (which turns out to be the only one you need for running radio) and a red one which was actually unplugged. My assumption was that this red wire was for either telephone and or gps.

 

[richard]

Its in the roof antenna as peten2005 points out.
There can be FM/AM, phone, and GPS antenna in there (European market, may be more for USA sat-radio etc) and possibly DAB-L in markets that had DAB-L (local DAB, DAB Band-III is what we use here). He's lucky to have resurrected it - they normally can't be as water has got into the coax cables
R

 

[Grandy]

Hi there, I’ve actually fixed this problem and the radio is now running perfectly. Turns out the amplifier is actually situated inside the base of the antenna (the little housing underneath the antenna whip). Water somehow made its way into the base and corroded part of the PCB. A good cleaning with some soldering seemed to have fixed the problem for me. (view attached image). To remove the base, I popped the interior head lamp cover (at the rear of the car) off and gained access to a nut that was holding the base in place. To gain access to the wires, I pulled the headliner from the rear of the car and immediately saw the connection. There was one brown wire (which turns out to be the only one you need for running radio) and a red one which was actually unplugged. My assumption was that this red wire was for either telephone and or gps. View attachment 126224

Hi thanks for that information I’ve taken my old aerial base off and just like yours it’s ringing wet inside I’ve ordered a new one and you give me hope the problem may
be cured now. The nut securing the base to the roof also seemed to be loose and not tight maybe that was the problem Thanks again

 

[peten2005]

Hi thanks for that information I’ve taken my old aerial base off and just like yours it’s ringing wet inside I’ve ordered a new one and you give me hope the problem may
be cured now. The nut securing the base to the roof also seemed to be loose and not tight maybe that was the problem Thanks again

No problem, happy to help.