RD4 Radio

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tomc71
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RD4 Radio

Post by tomc71 »

Hello, does anyone on the forum know if a RD4 CD/Radio will respond once a 12v current is applied to pin 11 (and earthed at pin 16) i.e. lights etc.

I am trying to diagnose why there is no link between the BSI and the radio, is the radio dead or is it switched on by the CAN? (I also have no central locking which may be associated), I have used Lexia to link the key but again the BSI is not seeing a "high frequency receiver".

The radio is an eBay purchase (RD4 M01) replacing a very bodged after market radio and telematics system, had to buy and refit the quadlock connector.

Car is a 2008 C2 VTS.

Many thanks in advance.

Tom

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GiveMeABreak
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Re: RD4 Radio

Post by GiveMeABreak »

The RD4 radio is also interfaced with the multifunction screen and requires that connection to work properly also.

tomc71
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Re: RD4 Radio

Post by tomc71 »

Hi Marc,
Thank you for the response, when I run Lexia Global Test the faults that come up on the BSI and the MFD show no connection to the radio. I am trying to work out if this is due to a wiring fault or because the head unit I bought is simply not working.

I do know that the head unit is getting power and earth to the appropriate pins but still nothing is happening, (e.g. trying to eject a disc that is in the head unit). Do you know if the head unit would have some function without being connected to the BSI/MFD? The CAN feeds also seem to be getting power, (CAN high is at 4.5volts and CAN low at 0.5 Volts).

Thanks,

Tom

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GiveMeABreak
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Re: RD4 Radio

Post by GiveMeABreak »

You may well have a duff unit. These and the earlier units fitted to the Xsara Picasso commonly had issues with stuck CDs that wouldn't eject. Had to replace a few of these on friends cars as they kept chewing up CDs.

But going back to your connection issue, be aware that there were CAN CAN and CAN VAN versions of multiplexed systems on the C2. If you don't have the correct screen and head unit it wont work as the electrical architectures are different.

Hell Razor5543
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Re: RD4 Radio

Post by Hell Razor5543 »

Hi, and :welc: to the Forum.

If you post up the VIN here forum staff can then look up your vehicle and tell you a LOT about it when she rolled out of the factory (including the radio architecture). Because of the way the PSA now charges for access to their database you may be asked (by the Forum) for a donation, but this will then cover you for up to two years of enquiries.

The VIN will automatically be obscured, so only forum staff can read it. Here is an example; VF7**************[VIN obfuscated, can be read by forum staff]

tomc71
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Re: RD4 Radio

Post by tomc71 »

Vehicle VIN is VF7**************[VIN obfuscated, can be read by forum staff]
Thanks,
Tom

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GiveMeABreak
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Re: RD4 Radio

Post by GiveMeABreak »

Ok, so you have a full CAN (CAN CAN) system with VDO RD4 system and MFD display that doesn't support Hands Free.

wheeler
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Re: RD4 Radio

Post by wheeler »

You cant mix the head unit types up as the VAN/CAN units have ISO type connector & the full CAN have a quadlock type connector.
Are you 100% you have rewired the new quadlock connector correctly? Was it completely cut off?

tomc71
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Re: RD4 Radio

Post by tomc71 »

It was completely cut off and I bought a second hand quad connector (from a 2007 c2) from a breakers on Ebay.

I rewired it colour to colour as best I could, the only difference was that, (according to RD4 Pin diagrams from the internet) the Can Low, (pin 13) was a slightly different colour on the car wiring to that on the re-used quadlock connector, (I could not find one the same). I also have a switched 12v positive on pin 15 which is showing as "not used" in RD4 diagrams.

Recorded voltages (wire to earth) with the ignition on were:
PINS 1 to 8 = 0V (speaker cables)
PIN 10 4.5 v (can high ?)
pin 12 12.6 v
pin 13 0.5 v (can low?)
pin 15 12.6 (switched via ignition)
pin 16 (Earth)

Thanks.

tomc71
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Re: RD4 Radio

Post by tomc71 »

The replacement head unit I bought was a Siemens RD4 N1 M02, not sure if the N1 M02 bit makes a difference.
What I am hoping to find out is if I apply a positive and ground to the right pins would the CD Eject, (or any other function not requiring the MFD) work? This may indicate that the unit itself is duff which will allow me to move onto other potential causes, (e.g. BSI which had been messed around with, (cover drilled and a twin cable soldered into it to support what looked like some kind of telematics set up which has now been removed, radio did not work prior to removal fyi).
For information, horn and central locking don't work either but car starts and runs fine). The MFD also works but obviously only shows time, date and temperature, no radio functions).

tomc71
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Re: RD4 Radio

Post by tomc71 »

Have now tested head unit on a friends C3, it works fine, (albeit beeping as expected). Can I now only assume that the BSI is at fault and send it off?

tomc71
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Re: RD4 Radio

Post by tomc71 »

SOLVED!
For those that are interested the solution was a simple one, the scrap quadlock connector that I bought had a red wire connected into pin 10, (can low) and a greenish yellowish wire connected into pin 13 (can high). On reinstalling the connecter I matched wire colour to wire colour however, after looking at a C3 wiring I saw that they had these reversed so thought I'd try switching the two over and bingo! The MFD now sees the stereo as does the BSI and all works!

Still no central locking despite reprogramming the keys in via Lexia and trying the 10 second hold technique many times... Lexia states that there is "No dialogue with the high frequency receiver" does this form part of the coms unit? All other coms functions, (indicators, wipers, lights, starting (and now stereo controls!) all work although the horn is still out of action.

Would the coms unit be the best place for further investigation, (a local locksmith has advised the keys are putting out a strong signal)??

Many thanks again for your help.

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Re: RD4 Radio

Post by GiveMeABreak »

Ok, so that's something we didn't know, but could of mentioned had we known - PSA wiring codes are not to be relied on because they can change colour and often do. Always better to use the pin allocation numbers in the connectors to ensure the connection is correct.

Glad you have that sorted.

Just for reference, you don't actually hold the fob button down for 10 seconds - that's internet waffle that's gone 'arse about face'. When pairing with the key in the ignition and turned to ignition on - you must press the lock button within 10 seconds.

But are we talking about a new aftermarket fob you are trying to code or the original fobs that came with the car? The most common failures of aftermarket fobs are that they don't have the correct circuitry for the remote locking or are of the wrong frequency.

tomc71
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Re: RD4 Radio

Post by tomc71 »

Hi Marc, to the best of my knowledge, (I've had the car for 3 weeks now) the key is original, it runs through the key set up in Lexia with no problems and starts the car so presumably the transponder is (if not original) then at least the right one for the car.
My concern is that the "High Frequency Receiver" listed in Lexia as part of the Global Test is just simply not seen, not sure where this is located or even if my assumption around this being responsible for central locking is correct....

Thank you, Tom

wheeler
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Re: RD4 Radio

Post by wheeler »

There is no separate HF receiver on your car so it’s normal for no dialogue. The HF receiver is integrated into the coms unit at the steering column. Ive yet to ever see or hear of one failing on the HF receiver side of things though.