XJ XJ6 / XJ8 / XJR ( X350 & X358 ) 2003 - 2009

Car not starting after key fob replacement

Thread Tools
 
Search this Thread
 
  #1  
Old 09-02-2020, 11:05 AM
karenh's Avatar
Junior Member
Thread Starter
Join Date: Jun 2015
Location: Sachse, TX
Posts: 7
Received 1 Like on 1 Post
Default Car not starting after key fob replacement

Hello there everyone, can someone please help me? My original key fob has stopped working. I ordered one on ebay switched out the blades only to find out that the new key fob was not compatible with the car. I switched the blades back and try to start the car it will not start. I tried to reprogram the old fob and i guess since it is sticky and one componet in there needs soldering it will not pair. I used the light blinking technique to reprogram the fob and i can hear the last two beeps like it is in program mode, however when i push the buttons on the fob they don't cause any reaction. Is this causing the car not to start? If i get another fob that is compatible will that work. Please help me.
 
  #2  
Old 09-02-2020, 11:31 AM
Wingrider's Avatar
Veteran Member
Join Date: Sep 2016
Location: Stow Ohio
Posts: 3,271
Received 798 Likes on 670 Posts
Default

The fob, the part with the buttons, has no part in starting the car, you have another issue.
 
  #3  
Old 09-02-2020, 12:12 PM
karenh's Avatar
Junior Member
Thread Starter
Join Date: Jun 2015
Location: Sachse, TX
Posts: 7
Received 1 Like on 1 Post
Default

That's what i was thinking, it's the same blade. It turns over with all lights but it says nothing. It was cranking before i switched the blades. I read somewhere that whenever you insert a new key, the car will remember that key. I did insert the new key but it didn't turn because it was not cut. So are you saying that even if i had the old key on the new fob that wasn't compatible or the original fob that has stopped working it should still start? So it doesn't need reprogramming?
 
  #4  
Old 09-02-2020, 12:39 PM
Rickkk's Avatar
Senior Member
Join Date: Mar 2014
Location: Michigan
Posts: 646
Received 100 Likes on 88 Posts
Default

The original key blade is specific for that vehicle only. As for the key fob which you purchased on eBay, check the key fob battery first. If the battery checks okay, try spraying a little Radio Shack Cleaner & Lubricant (Cat No. 6400148) over those key fob switches.
 
  #5  
Old 09-02-2020, 01:14 PM
karenh's Avatar
Junior Member
Thread Starter
Join Date: Jun 2015
Location: Sachse, TX
Posts: 7
Received 1 Like on 1 Post
Default

Ok, do you think it's possible that the key may need reprogramming?
 
  #6  
Old 09-02-2020, 01:42 PM
karenh's Avatar
Junior Member
Thread Starter
Join Date: Jun 2015
Location: Sachse, TX
Posts: 7
Received 1 Like on 1 Post
Default

Ok, but do you think that the key may need programming again?
 
  #7  
Old 09-02-2020, 02:09 PM
Partick the Cat's Avatar
Veteran Member
Join Date: Apr 2013
Location: Gloucestershire, England
Posts: 1,055
Received 306 Likes on 224 Posts
Default

1. It's not the key that needs programming (you can't 'program' keys) - it's the car that has to be programmed to recognise the key.

2. The fob has two chips in it, and both need to be registered with the car.

One is the remote chip which is battery powered and locks and unlocks the doors, and is nothing to do with starting the engine.

The other is a transponder which is energised by a coil around the ignition lock. Think of it as the same as an I/D chip that you'd have injected into a cat or dog's scruff. That's the beastie which tells the car that the mechanical key is genuine.

If the transponder isn't registered with the car then it won't start even with the correct mechanical key (your situation, I think).

If you have two keys with transponders already registered in the cars electronics then there is a procedure for registering further key transponders, but it won't work if you only have one, or none. In that case you need to use Jag software called SDD. There are quite a few posts about this if you use the 'Search' facility on this forum.
 

Last edited by Partick the Cat; 09-02-2020 at 02:17 PM.
The following 2 users liked this post by Partick the Cat:
karenh (09-02-2020), motorcarman (09-02-2020)
  #8  
Old 09-02-2020, 10:38 PM
karenh's Avatar
Junior Member
Thread Starter
Join Date: Jun 2015
Location: Sachse, TX
Posts: 7
Received 1 Like on 1 Post
Default

Thank you, i only have 1 key and it is in bad shape, would i need a locksmith?
 
  #9  
Old 09-03-2020, 02:48 AM
klfong's Avatar
Senior Member
Join Date: Mar 2010
Location: Singapore
Posts: 330
Received 43 Likes on 31 Posts
Default

Originally Posted by Partick the Cat
1. It's not the key that needs programming (you can't 'program' keys) - it's the car that has to be programmed to recognise the key.

2. The fob has two chips in it, and both need to be registered with the car.

One is the remote chip which is battery powered and locks and unlocks the doors, and is nothing to do with starting the engine.

The other is a transponder which is energised by a coil around the ignition lock. Think of it as the same as an I/D chip that you'd have injected into a cat or dog's scruff. That's the beastie which tells the car that the mechanical key is genuine.

If the transponder isn't registered with the car then it won't start even with the correct mechanical key (your situation, I think).

If you have two keys with transponders already registered in the cars electronics then there is a procedure for registering further key transponders, but it won't work if you only have one, or none. In that case you need to use Jag software called SDD. There are quite a few posts about this if you use the 'Search' facility on this forum.


Hi Partick, will the IDS work for this registering procedure?

 
  #10  
Old 09-03-2020, 04:22 AM
Partick the Cat's Avatar
Veteran Member
Join Date: Apr 2013
Location: Gloucestershire, England
Posts: 1,055
Received 306 Likes on 224 Posts
Default

IDS was (as I understand it) the earlier version/name for SDD, so I guess that should be able to do it.
 
  #11  
Old 09-03-2020, 07:07 AM
Wingrider's Avatar
Veteran Member
Join Date: Sep 2016
Location: Stow Ohio
Posts: 3,271
Received 798 Likes on 670 Posts
Default

Some locksmiths can cut and program our keys.
But there is only one in the Akron Ohio area i know of.
They charge by the make of car, i was told, when i asked.
Jaguar keys are double the similar Ford keys in price.
 
  #12  
Old 09-03-2020, 10:38 AM
benzjag's Avatar
Senior Member
Join Date: Feb 2013
Location: Rocky Mount, NC
Posts: 139
Likes: 0
Received 27 Likes on 16 Posts
Default

If the key part (upper half) of the FOB is the original that came with the car and the lower part of the FOB is for remote opening/closing of the doors, why doesn't the car start even though the lower part is broken (and will not remotely open/close the doors)?
 
  #13  
Old 09-03-2020, 12:12 PM
Partick the Cat's Avatar
Veteran Member
Join Date: Apr 2013
Location: Gloucestershire, England
Posts: 1,055
Received 306 Likes on 224 Posts
Default

Because the lower part of the fob only has the 'remote' chip in it and that has nothing to do with starting the car.

Starting is a function of the transponder which is hidden inside the top part of the fob, the bit with the key. You need a key (which fits and turns the ignition lock, obviously) with a transponder attached, a transponder which has been 'programmed' into the car's system.
 
  #14  
Old 09-03-2020, 02:42 PM
Fraser Mitchell's Avatar
Veteran Member
Join Date: Dec 2009
Location: Crewe, England
Posts: 9,409
Received 2,451 Likes on 1,949 Posts
Default

Partick is absolutely correct. When I bought a 2nd key, I had to take it to the main agents for programming so it would work with the car. They obviously had the car details to work with. They also told me that any lost keys will no longer work when the new keys and any existing key still in use, are re-programmed.
 
  #15  
Old 09-03-2020, 03:59 PM
karenh's Avatar
Junior Member
Thread Starter
Join Date: Jun 2015
Location: Sachse, TX
Posts: 7
Received 1 Like on 1 Post
Default

UPDATE:
First i would like to say thank you to all of you guys for your support and time. The car is starting now. Somehow when i was changing the blade it came out and i sat it down and didn't really pay any attention to it. I tried to take the fob piece off first, thinking i was unable to knock the pin out to remove it that way and that's how i ended up with that part loose. When you responded about that the transponder, it donned on me then. Thank you so much
 
The following users liked this post:
Partick the Cat (09-04-2020)
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
sam1977
XJ XJ6 / XJR6 ( X300 )
3
02-08-2020 03:05 AM
Ray1000
XK8 / XKR ( X100 )
33
06-25-2018 02:11 PM
MikeinPa
X-Type ( X400 )
4
02-06-2016 07:55 AM
redxk8
XK8 / XKR ( X100 )
1
09-30-2015 08:18 AM
asm54
XJ XJ6 / XJR6 ( X300 )
0
11-21-2011 04:32 PM

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 


Quick Reply: Car not starting after key fob replacement



All times are GMT -5. The time now is 10:26 AM.