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Keyless go expert please

4K views 13 replies 4 participants last post by  eric242340 
#1 ·
Hi, just got car back from dealers who fixed my SRS and looked into why my keyless go is not working. It has never worked since I have had the car so have zero knowlege on what should happen apart from the numerous posts I have read. I have replaced the KG module in the boot (2nd hand unit) due to water ingress. The 1 card I have shows 2 green lights when I push the button. I have all the KG equipment fitted to the car and tested working in STAR. Key not recognised in the dash when I open a car door. I asked the dealer to investigate and they said I would need a new EIS in order to possibly fix the problem but no guarantees (£800+). They said they could not communicate with the EIS that's why I would need a new one. I can access the EIS with no issues, read the key tracks etc so am a tad confused. If any expert can talk me through coding the card to the EIS / KG module and finally get the thing working that would be great. It's not the end of the world as I've never had KG so don't miss it but as it's installed on the car it would be nice if it functioned, many thanks as always, Ian
 
#2 ·
This is not part of the EIS other than the EIS has to recognize that the keyless go ECU is there. The first simple test on STAR is to place the 2 cards in the car, go to set "keyless go", then wait 5 mins, if the result says keys not found.

At the same time while on STAR and a quick test if the keyless locking ECU had a problem it would say so, it would also tell you if a door handle was at fault.

many dealers just do not understand the keyless go part.
 
#3 ·
Hi Malcom, I only have 1 card that I found in the owners wallet - sealed in MB parts bag so I think never used. I think the previous owner bought it thinking KG would work but it was the damage to the KG module due to water that would have caused any problems. So with 1 card that SDS does not recognise how would you proceed please? I think I just need the KG module to recognise the card I have by some means, many thanks, Ian
 
#4 ·
Again with just the one card, it is placed in the car and on STAR you just go to the menu for programming that key and see if it will, now one thing here, did the new ECU need to be SCN coded to the car, if this is the case then the car needs an on line STAR to code this too the car. If any ecu the needs to be SCN coded and this is not done, when doing a STAR check, STAR will not find the ECU on the car, it will pass over it and not find it.
 
#5 ·
The new KG module was recognised by the car without coding. I can read the KG tracks it just does not recognise my card. All the tracks in the EIS are enabled and used and KG module shows 2 tracks used. I have not yet proved that the card I have works as no way of testing. All it does it shows 2 green lights when I pust the button. I have tried pressing the card button for over 10 seconds but it always shows these 2 lights (they go off after 2 seconds or so) - is this correct?
 
#6 ·
The button on the card should display the mode of the car in the way that it locks, from memory you can press both buttons on the card to make one door or both to open. from memory it does show a red indication when car unlocked, something like that.

Hard to know if the card is at fault, cards were supplied up to mid 2003 I think, your car certainly
 
#7 ·
The red bit is where you failed, it should have been a new unit and does need scn coding to your car. Do you still have the original unit that was affected by water ingress?
 
#8 ·
The actual key data is still held in the EIS, but the keyless go module requires the same data, when fitting one there is nothing to do on STAR the procedure is in the enclosed file.

I do not know if they can be reprogrammed, nothing for STAR so probably will never need SCN coding as STAR is not required in the first place.

You would never know all this without this document


I would unplug the module and try what this says.
 

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#9 ·
Help Mr Television Keyless Go expert

HAve both original key fobs and two wallet keys, they all worked fine, unlocked doors, start car with shifter button.
Dash said batteries in key fob were low so I changed out both fobs and one wallet. Now keyless go will not recognize any of the key fobs or the one wallet card. Also cannot unlock doors by just pressing external door button. Key fobs lock, unlock by pressing butons and will start car by inserting in ignition.
The one wallet card I did not change batteries in works prefect still.
What do I need to do to get the fobs and wallet card working again normally?
Thanks so much for any help!!!!
 
#10 ·
Number one rule with these keys and cards, they only work well by using branded batteries, Panasonic, Duracell etc, the cheap ones on cards do not work.

The actual key fob has nothing to do with keyless go at all. Are the batteries fitted correct way up, does the LED in the key flash, is there a beam as seen in a camera.

Re the card, does the led light when any button pressed
 
#11 ·
The key fob lock,unlock and trunk buttons work perfect. BUt when sitting on center console, the start button in shifter will not start the car. Both would start the car before I changed batteries. I know the keyless go works because the one wallet card I did not change batteries in, still starts the car.
 
#12 ·
Read what Malcolm (Television) posted and respond accordingly. You changed the batteries in 3 and now they do not work, you did not change the batteries in 1 and it still works, does this not ring alarm bells?
 
#13 ·
Used Energizer batteries and they read 3.07v. Doubled,and triple checked them. Button functions work perfect from 30ft away, but proximity unlock and keyless go do not anymore.
I know the proximity and keyless go work because they work with the one wallet card.
I know the fobs are working because all button functions work.
It is like the fobs and one wallet card lost sync with the car computer when I changed the batteries.
 
#14 ·
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