2004 Citroen Relay Key Infra Red Transponder / receiver unit Location

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bnd
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2004 Citroen Relay Key Infra Red Transponder / receiver unit Location

Post by bnd »

Do any of you fellow members know where the infra red ignition key reciever/ transponder unit is situated in the van. I dont know the location of the infra red receiver unit for the signal from the key to activate the central locking is. There is a small black unit in the centre of the dash below the flip up clip board, but I'm unsure if thats it. The transponder for the key to marry and read the chip in the key for the van to start is working ok as If it wasnt the van would not start. It does. The key opens and shuts all the doors manually and red light illuminates on the key fob when any if the keys for the central locking are pressed.

I have just got the van back from a citroen dealer who says it's either the key itself or the infra red reciever that's not working. They said they couldn't tell which fault it was, yet before leaving the van in with them they told me they had a device that could confirm that the infra red signal was being sent from the key or not, yet they now tell me they cannot and need possibly a new key and receiver unit to make sure it works. They gave me the prices and all I can say is that I had to get plugged into a cardiac arrest unit after being told.

I have had 3 guys (aledged remote locking and key cutting experts and none of them can sort the problem out including a office citroen dealer) so I'm going to try and start with checking the wiring etc but need to know we're this unit lives in the van.

Any pointers would be greatly appreciated.
Last edited by bnd on 21 Jul 2020, 13:07, edited 1 time in total.

Hell Razor5543
NOT Alistair or Simon
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Re: 2004 Citroen Relay Key Infra Red Transponder / receiver unit Location

Post by Hell Razor5543 »

There is a simple way to see if the key is transmitting an IR signal; your smartphone! Simply load up the camera app, point the key at the camera lens, press the button and watch the screen. If you see a pinkish light flashing that would show the key is transmitting.

Be aware that some smartphones may not 'see' the IR LED flashing (iPhones seem to be the worst for this).

bnd
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Re: 2004 Citroen Relay Key Infra Red Transponder / receiver unit Location

Post by bnd »

Thanks for that James. I have just tried it with my Samsung j3 pro and it looks like the key isn't transmitting.

Hell Razor5543
NOT Alistair or Simon
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Joined: 01 Apr 2012, 09:47
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Re: 2004 Citroen Relay Key Infra Red Transponder / receiver unit Location

Post by Hell Razor5543 »

OK, so that is 'useful' to know. At least (with a bit of care) you might be able to repair it. The IR receiver should have a small black dome sited somewhere it can 'see' the IR signal from the key. A good location (although it is not always here) is in the ceiling close to where the rear view mirror is.

bnd
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Re: 2004 Citroen Relay Key Infra Red Transponder / receiver unit Location

Post by bnd »

Your a gent. Thank you so much.

wheeler
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Re: 2004 Citroen Relay Key Infra Red Transponder / receiver unit Location

Post by wheeler »

The Mk2 Relay uses an RF transmitter not IR so thats why you cant see the signal.
There are devices that can check the RF signal from the remote, any half decent garage should have one.
Is it just the remote part of the central locking thats not working? the van starts normally?
How many keys do you have for this van?

Hell Razor5543
NOT Alistair or Simon
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Joined: 01 Apr 2012, 09:47
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Re: 2004 Citroen Relay Key Infra Red Transponder / receiver unit Location

Post by Hell Razor5543 »

OK, so that is why you cannot see an IR LED flashing. However, I would have thought a Citroen dealership should have known that the later model van would use RF rather than IR.

bnd
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Re: 2004 Citroen Relay Key Infra Red Transponder / receiver unit Location

Post by bnd »

The citroen dealer (Stoneacre Wrexham) have assured me that this vehicle uses IR not RF. Its a 2004 model. I spoke to a chap this afternoon who has a xhorse IR sector and the key is definitely pushing out a strong IR signal, so it just leaves the reciever. The guy doesnt know where it is located so its a matter of replacing it when found and coding it via the software to match the key and receiver. I have looked everywhere for it. I only have one key and the van starts and locks with this key manually. It's just the remote locking / opening is not working.

wheeler
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Re: 2004 Citroen Relay Key Infra Red Transponder / receiver unit Location

Post by wheeler »

OK, just checking the details here, this is a 2004 mk2 Relay van & it has a rectangular key with flip out blade?
If the answer to all above is yes then im 99% sure this is RF & not IR, The last Citroen im aware of to use an IR plip was the early pre facelift Saxo.
If it was IR there should be an 'eye' on the remote to transmit & as IR needs line of site the receiver should be visible, they are almost always in the centre front of the roof area where the interior light is.
Most remote testers check both IR & RF, is it possible it was picking up the RF signal?
The first thing i would try is re pairing the remote, this is done with Lexia & needs a 5 digit passcode, note that the passcode is different to the immobiliser code thats on the blue code card for programming transponder keys, The remote & transponder key are programmed separately on the Fiat system.
I think there is a multifunction control unit behind the glovebox that incorporates the RF receiver on these vans.
If i have the last 8 digits of your VIN i can check a wiring diagram & confirm.

P.S. Has the remote locking ever worked since you have had the van?

bnd
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Re: 2004 Citroen Relay Key Infra Red Transponder / receiver unit Location

Post by bnd »

Hi wheeler. I think you have hit the nail on the head as there is no "eye" on the key. It is indeed a flip out key blade and when you press either of the buttons on the key a red light comes on and then flashes red if you hold either of the buttons down. The remote locking has never worked since I got the van. I had a head on argument at the dealership as they were being paid to find the problem and fix it. I got the van back the same way I left it in. It's a cop out for them to say it was up to me to either take a chance and order a new key or order a new receiver or both. That's why I left the van in to them in the 2st place for them to find the fault and fix it. I have been making a few phone calls this evening and what you are saying rings very true. Thank you one gut I rang told me that the dealers are mostly useless. All i know is my bank accountis lighter than it wss yesterday.

bnd
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Re: 2004 Citroen Relay Key Infra Red Transponder / receiver unit Location

Post by bnd »

I got a piece of paper with the key codes on it for the van. The dealer confirmed they were correct

bnd
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Re: 2004 Citroen Relay Key Infra Red Transponder / receiver unit Location

Post by bnd »

Last 8 digits of the vin are 17503708

wheeler
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Re: 2004 Citroen Relay Key Infra Red Transponder / receiver unit Location

Post by wheeler »

There is an electric window/central locking control unit (number 6228 in the diagram), i suspect this will also incorporate the RF receiver. The diagram isnt too clear to its location but it looks like it is between the glovebox & heater unit area, it should have a 24 way black connector on it to help identify but may also have extra plugs.
First thing I would try is re-pairing the remote but I would have hoped the dealer would have already tried that?? you need Lexia for this. Next i would replace the key as you need a spare anyway regardless & take it from there. In general its is usually cheaper to get a replacement transponder key/remote if you already have a working key, if you lose/damage
your only working key its often lots more £££ to get a new one.
Attachments
relay2.jpg

bnd
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Joined: 30 Jun 2016, 17:15
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Re: 2004 Citroen Relay Key Infra Red Transponder / receiver unit Location

Post by bnd »

This is so helpful wheeler I'm indebted to you. I will try to get to the bottom of this. It may take a bit of time but I will come back and report my findings/ outcome.

bnd
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Joined: 30 Jun 2016, 17:15
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Re: 2004 Citroen Relay Key Infra Red Transponder / receiver unit Location

Post by bnd »

Well, I have got to the bottom of this at last. Central locking is now working perfectly remotely and manually.

The problem was the eeprom chip in the RF receiver. I managed to get a new RF receiver and matching key fob chip from a breaker for £45.

This central locking system is essentially a fiat system. No software was required as the chip and receiver unit were working on the van that was broke up in the breakers yard, so they were already paired. If you cannot get a matching key chip and receiver unit all is not lost as you can get them paired but it requires the correct software like Lexia. Normal programming procedures aren’t an option and as there is a chip known as an eeprom chip in the reciever and it needs to be programmed. Work needs to be done to pair them. (specific key data and security codes extracted from the vans ECU or immobiliser and then written to the transponder).

The central locking control unit is sited behind the glove box. You have to remove the glove box and associated panels to get access to it (part number 1356927080) The RF receiver is sited below the paper/document holder in the centre of the dash board that flips up. The radio has to be removed and the 4 screws holding the panel onto the main dash board panel. The RF receiver is held on by 2 screws (part number 1331247080) it has one small multiple pin connector.

I hope this helps someone else out there

Cheers everyone!

See photos on page 2 of this thread...
Last edited by bnd on 21 Jul 2020, 13:04, edited 6 times in total.