My spare key fob wasn't playing very well - seemed to only work occassionally. So using some information read on this forum I decided to open it up.

Only to find that pressing the buttons on the circuit board worked every time

Here is what I found inside:



 2002 Honda VFR800
2002 Toyota Celica 140 Silver (mid life crisis - again!)
2007 FL2 GS Manual Army Reconnaissance Green + freel2.com sticker
2004 Toyota Celica 140 Black - Gone
2000 Toyota Celica 140 Silver - Gone
1998 Toyota Celica ST Pearl Green - Gone
1996 Nissan Primera 1.6 - Gone
1994 Rover Montego 1.6 Auto - Gone

Yer, not much to it is there? The price we have to pay for a new one is a complete rip off.

An absolute to get open. Took ages then it just suddenly gave way.....

I suppose if they were made and sold by everyone they would be cheaper - and the programming is in the price as well.

Off to the £1.00 shop for some super-glue. 2002 Honda VFR800
2002 Toyota Celica 140 Silver (mid life crisis - again!)
2007 FL2 GS Manual Army Reconnaissance Green + freel2.com sticker
2004 Toyota Celica 140 Black - Gone
2000 Toyota Celica 140 Silver - Gone
1998 Toyota Celica ST Pearl Green - Gone
1996 Nissan Primera 1.6 - Gone
1994 Rover Montego 1.6 Auto - Gone

Very interesting. Would like to know what you used to open it up without destroying the case. It looks as though the battery is not a replaceable item. Connections appear to be spot welded and presumably it is a special rechargeable button cell charged by induction when in the vehicle slot. 2007 TD4 SE Manual
2014 TD4 HSE Auto

The battery is a VL2330 +3V button cell (this was stated correctly in another thread)

To get the case open I used stanley knife, small and large slotted screw driver. And a lot of force

It will look opened when it is put back together - so a bit of plastic magic will be needed once glued - and it becomes the "spare" - but not forgetting to use it occassionally to give it a charge. 2002 Honda VFR800
2002 Toyota Celica 140 Silver (mid life crisis - again!)
2007 FL2 GS Manual Army Reconnaissance Green + freel2.com sticker
2004 Toyota Celica 140 Black - Gone
2000 Toyota Celica 140 Silver - Gone
1998 Toyota Celica ST Pearl Green - Gone
1996 Nissan Primera 1.6 - Gone
1994 Rover Montego 1.6 Auto - Gone

I should add - I believe the battery connection is soldered! (needs to be confirmed)

The case back has a rubber insert which appears to apply pressure against the battery contact so I guess a battery could be put in and not soldered / welded. 2002 Honda VFR800
2002 Toyota Celica 140 Silver (mid life crisis - again!)
2007 FL2 GS Manual Army Reconnaissance Green + freel2.com sticker
2004 Toyota Celica 140 Black - Gone
2000 Toyota Celica 140 Silver - Gone
1998 Toyota Celica ST Pearl Green - Gone
1996 Nissan Primera 1.6 - Gone
1994 Rover Montego 1.6 Auto - Gone

Looking at the pictures of it on here there is a tag spot welded on to the cell then the other end of the tag is soldered to the contacts.
The reason for this is "HEAT" Heat will destroy the componds inside the button cell causing a greatly reduced life span and the ability to hold a charge.
Spot welding is intant with very little heat tranferance to the cell. Soldering, you have to get the surface of what you are soldering hot before the solder will stick, this process will transfere to much unwanted heat to the cell.

Just to add my 2 pennarth, you could always solder a strip on the circuit board then form it over the top of the cell and put a kink in it so when you glue it back together, the kink will act as a spring on the case and keep pressure onto the cell.

In the past, I have used the lever from a micro switch for this type of thing.

Good to know there is nothing unusual in the key fob from the look of it, though yours does look as though it may have had some water or condensation in it from the look of the circuit board.  MY2014 SD4 XS
Ipanema Sand

MY10 TD4-e GS Manual
Lago Grey Now retired after 8 trouble free years

scrimple wrote:

Just to add my 2 pennarth, you could always solder a strip on the circuit board then form it over the top of the cell and put a kink in it so when you glue it back together, the kink will act as a spring on the case and keep pressure onto the cell.

In the past, I have used the lever from a micro switch for this type of thing.

Good to know there is nothing unusual in the key fob from the look of it, though yours does look as though it may have had some water or condensation in it from the look of the circuit board.

On close inspection there is no trace of water or moisture damage - perhaps just not perfect pictures. But I do agree with your suggestion about replacing the contact arm.  2002 Honda VFR800
2002 Toyota Celica 140 Silver (mid life crisis - again!)
2007 FL2 GS Manual Army Reconnaissance Green + freel2.com sticker
2004 Toyota Celica 140 Black - Gone
2000 Toyota Celica 140 Silver - Gone
1998 Toyota Celica ST Pearl Green - Gone
1996 Nissan Primera 1.6 - Gone
1994 Rover Montego 1.6 Auto - Gone

Hi simont

Sorry, didn't mean to give the impression of damage.

It's just if you look at the circuit board there appears to be a whitish haze around and on a couple of components, I have noticed this before on boards that have been exposed to condensation.

It is not damage as such, but it can cause a reaction with the battery, and as you said it was playing up a bit, it could manifest as a bit of corrosion or dry joint on a component and work intermittently.  MY2014 SD4 XS
Ipanema Sand

MY10 TD4-e GS Manual
Lago Grey Now retired after 8 trouble free years

Congrats on adding to the knowledge base!
But, how did taking it apart solve the original problem?
The circuit buttons 'worked ok' On reassembly did the cover buttons now work?
Just curious
JT Upgraded to an ex demo, 7 mth old, Rimini Red/Ebony Napoli Auto HSE on 28th Jan 2011, added roof rails, mudflaps and side strips.
Gone - A great 57 Plate, Auto SE, Bought Feb 2009, Roof Rails and Mudflaps added on purchase. Blue colour, anything but drug dealer black.....

Hi Scrimple

I don't take offence too easily.

I think it is just bad lighting - The fob was tightly sealed. 2002 Honda VFR800
2002 Toyota Celica 140 Silver (mid life crisis - again!)
2007 FL2 GS Manual Army Reconnaissance Green + freel2.com sticker
2004 Toyota Celica 140 Black - Gone
2000 Toyota Celica 140 Silver - Gone
1998 Toyota Celica ST Pearl Green - Gone
1996 Nissan Primera 1.6 - Gone
1994 Rover Montego 1.6 Auto - Gone

julytourist wrote:

But, how did taking it apart solve the original problem?
The circuit buttons 'worked ok' On reassembly did the cover buttons now work?
Just curious
JT

It isn't quite fully assembled yet!

Haven't been able to figure that out yet - doesn't really make sense

Greatly worrying as I'm a trained 'electronics engineer'

I feel it is something to do with the fact that the rubber button has a X inside which presses against the micro switch on the PCB.

So I think I will leave it unglued for now and use it as a spare. 2002 Honda VFR800
2002 Toyota Celica 140 Silver (mid life crisis - again!)
2007 FL2 GS Manual Army Reconnaissance Green + freel2.com sticker
2004 Toyota Celica 140 Black - Gone
2000 Toyota Celica 140 Silver - Gone
1998 Toyota Celica ST Pearl Green - Gone
1996 Nissan Primera 1.6 - Gone
1994 Rover Montego 1.6 Auto - Gone

superspark wrote:

Looking at the pictures of it on here there is a tag spot welded on to the cell then the other end of the tag is soldered to the contacts.
The reason for this is "HEAT" Heat will destroy the componds inside the button cell causing a greatly reduced life span and the ability to hold a charge.
Spot welding is intant with very little heat tranferance to the cell. Soldering, you have to get the surface of what you are soldering hot before the solder will stick, this process will transfere to much unwanted heat to the cell.

Battery and tags...

The Answer

http://uk.farnell.com/jsp/displayProduct.j...2-00001000[/url]

and you can see the two soldered tags on the photo showing the component side. (bottom right and just above centre left) 2002 Honda VFR800
2002 Toyota Celica 140 Silver (mid life crisis - again!)
2007 FL2 GS Manual Army Reconnaissance Green + freel2.com sticker
2004 Toyota Celica 140 Black - Gone
2000 Toyota Celica 140 Silver - Gone
1998 Toyota Celica ST Pearl Green - Gone
1996 Nissan Primera 1.6 - Gone
1994 Rover Montego 1.6 Auto - Gone