C5 Bluetooth Oddity

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CaptainFluffy
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Joined: 12 Oct 2021, 10:53

C5 Bluetooth Oddity

Post by CaptainFluffy »

Hi all! I got a lovely 2010 C5 Exclusive with an RD4 today! It has the non-sat nav audio system (matrix display) and was wondering if your collective knowledge could help me out a little! I'm trying to stream music from my phone via Bluetooth. I have the phone all connected, and it is silent as if it's playing, but when I press the "mode" button on the headunit, nothing happens. Likewise if I put a USB drive in the socket!
Any ideas, please? I tried making calls, but even though it says there's a call in progress on the matrix screen, the car doesn't switch from radio to the phone. I've included some photos below!

Thank y'all!
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GiveMeABreak
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Re: C5 Bluetooth Oddity

Post by GiveMeABreak »

Is this the original RD4 head unit and display or have you changed it at all for an RD45? Pop your VIN up for me (automasked on post submission) it will help me determine what was fitted at factory.
CaptainFluffy
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Re: C5 Bluetooth Oddity

Post by CaptainFluffy »

I only got the car yesterday, but when I removed it, the date was 2014 (the car is a 2010) so I can only assume that a previous owner has replaced it. (I took another photo!) Here's the VIN: VF7**************[VIN obfuscated, can be read by forum staff] Thank you!
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Last edited by GiveMeABreak on 12 Oct 2021, 12:16, edited 1 time in total.
Reason: Corrected VIN
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GiveMeABreak
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Re: C5 Bluetooth Oddity

Post by GiveMeABreak »

Ok, so your C5 was originally shipped with the RD4 system and a telephone interface kit (bluetooth) separately and wired behind the dash.

So maybe somebody has replaced the display at some point given the build date of your car. You can always try unpairing AND deleting the phone from both the Head Unit and also the Mobile (unpairing is not enough - it must be deleted). Then restart the phone and the car and try pairing up again and make sure you select all the profiles you want on the phone when the bluetooth connection is made.

It may take a while to synchronise contacts etc.

If possible I would also try pairing a different phone if you have access to one and see if that works or not.
CaptainFluffy
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Joined: 12 Oct 2021, 10:53

Re: C5 Bluetooth Oddity

Post by CaptainFluffy »

Thank you Marc! I'll try another phone, My daughter has an older S7. I tried unpairing and deleting and it didn't work. I even tried the reset procedure for the ECU (all that did was throw my clock back to 2007!) I found the bluetooth module behind the odds and ends cubby, unplugged that and my phone wouldn't even connect (as expected) so I know everything is all there. The phone is silent when making calls and connected (I called the speaking clock!) and as you can see, it shows on the matrix screen that a call is in progress. It's simply that the source button doesn't work (although if I DO press it, the FM radio/song/station information that scrolls along the bottom of the display resets to the start of the scroll). Is there a physical connection on the rear of the unit that connects directly to the bluetooth module ( aside from the grey MP3 one) do you know?
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GiveMeABreak
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Re: C5 Bluetooth Oddity

Post by GiveMeABreak »

There is, as on the RD4s (before the RD45 which had bluetooth built into the Head Unit, negating the need for a separate hands free kit) there needs to be a physical connection from the Hands Free Kit to the RD4 in order to pass the signals back that it is receiving via bluetooth. So I would be checking the quadlock connections carefully and making sure there are not loose pins or wires.
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xantia_v6
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Re: C5 Bluetooth Oddity

Post by xantia_v6 »

The unit in the photo in the original post is an RD4. The RD45 has a MUTE button to the right of the CD slot
RD45 panel
RD45 panel
CaptainFluffy
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Re: C5 Bluetooth Oddity

Post by CaptainFluffy »

GiveMeABreak wrote:
12 Oct 2021, 23:42
There is, as on the RD4s (before the RD45 which had bluetooth built into the Head Unit, negating the need for a separate hands free kit) there needs to be a physical connection from the Hands Free Kit to the RD4 in order to pass the signals back that it is receiving via bluetooth. So I would be checking the quadlock connections carefully and making sure there are not loose pins or wires.
I'll be doing that as soon as I have mu coffee, lol! I found a few pinout diagrams, so I'll check the Aux2 pins etc. (if I can find my multimeter, lol!) as they are apparently the ones for the bluetooth. (Disclaimer, I have VERY limited knowledge on electronics, lol!)

Failing all this, would an RD45 be a straight swap? I presume I already have the mic etc. I'd also assume that if I did put an RD45 in, I'd simply just have to disconnect the external BT module?
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xantia_v6
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Re: C5 Bluetooth Oddity

Post by xantia_v6 »

The RD45 is an easy swap, but the microphone cable on your car will be going to the external Bluetooth module, not the connector on the radio head. The easiest DIY fix is to buy an RD45 microphone cable and run it from the microphone to the head unit.
CaptainFluffy
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Re: C5 Bluetooth Oddity

Post by CaptainFluffy »

Thanks! I'll do that if I go down that route! Well..here's a little update, but it only serves to ask MORE questions! I looked at the pins and compared them to a pinout diagram. There seems to be 2 extra pins that have been cut off. They're soldered to the PCB, but are outside the main pins (numbered) and don't seem to connect to anything! Any ideas? When I looked initially, I thought they might have been the aux2 audio pins (pins #1 and #7) which were used for the bluetooth, but the plastic has small numbers on it that say the other 2 pins are 1 and 7...

My brain is melting, but I'm grateful to everyone!
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GiveMeABreak
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Re: C5 Bluetooth Oddity

Post by GiveMeABreak »

Ignore those, it's by design. Here is the Pin-Out for the RD4 system for CD Changer and Hands Free Kit, but without HiFi Option:

16-way black connector
Channel No.Description
D1-
D2-
D3-
D4-
D5-
D6-
D7-
D8-
D9-
D10COMFORT CAN
D11-
D12Battery + supply
D13COMFORT CAN
D14-
D15Switched battery+ supply
D16Earth

12-way black connector
Channel No.Description
1Earth : Compact disc changer
2CAN Low : Compact disc changer
3Permanent + : Compact disc changer
4CD control : Audio (Right hand )
5-
6-
7CAN High - Compact disc changer
8Audio control - Earth
9-
10CD control : Audio (Left hand )
11-
12-


12-way connector
Channel No.Description
1Audio auxiliary (Right hand )
2Audio earth
3-
4Hands-free kit : Audio -
5-
6-
7Audio auxiliary (Left hand )
8-
9-
10Hands-free kit : Audio -
11Hands-free kit : Audio +
12-


8-way black connector
Channel No.Description
1control + Rear right speaker
2control + Front right speaker
3control + Front left speaker
4control + Rear left speaker
5control - Rear right speaker
6control - Front right speaker
7control - Front left speaker
8control - Rear left speaker
CaptainFluffy
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Re: C5 Bluetooth Oddity

Post by CaptainFluffy »

I think I've actually solved my issue...I looked at the lead, as opposed to the unit. Part B (the bottom left) connector doesn't actually have any wires going to those pins! Which would explain the no sound coming out of it even though it's connected. I assume the lead is easy to replace?
CaptainFluffy
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Re: C5 Bluetooth Oddity

Post by CaptainFluffy »

Does anyone know if there's a lead that I can get with the correct pins from the rear of the RD4 to the factory bluetooth module?