Remote Key Transmitter Fix

[brent]

My key transmitter for the remote door locks stopped working like many others already listed on this forum. I switched to the other key that came with the car and in 3 years it stopped working too. I changed batteries with no improvement. I reset the key per the manual and no improvement. I turned the battery upside down in the remote to force a reset and no improvement. I noticed that the LED worked but the door lock didn’t operate. I disassembled the remote and tried it without the key just the transmitter, low and behold, it worked!

Further troubleshooting revealed that the retainer for the battery didn’t hold adequately. Using the transmitter physically separate from the key allows your fingers to support the battery as you press the button. Apparently the LED requires much less power than the transmitter and a poor contact would fire the LED but not the transmitter. My keys are almost 10 years old. I have 125,000 miles on my 98 Boxster and I am the original owner. The keys have been used a quite a few times and the buttons have worn smooth. I measured the transmitter and the key fob and found the battery is not supported in the key fob other than by the plastic battery retainer clips of the battery socket on the circuit board. I used a piece of chewing gum between the battery and the case, snapped the halves together, disassembled and measured its thickness. I inserted a shim behind the battery, a round piece of foam about 3/32ths thick (I cut mine in half because it was too resilient and kept the key from assembling properly) and assembled the key and transmitter.

The remote lock now works seamlessly time after time. This shim supports the battery forcing contact in the battery socket. The foam disk I used is from the assortment of disks you buy at the local hardware store to protect your furniture from a lamp base or pottery. I also used it to shim the windscreen in the roll bar to stop them from buzzing. More commonly they are felt disks but I found some foam ones. You could also fold some tape until it is the correct thickness and then cut it to fit and snap the key back together. It would be trial and error but easy enough to add or remove some tape and try again. It could be that the metal tangs on the side of the battery socket have fatigued to where there is poor contact or it could be the plastic battery retainer has done the same. In any case a two bit fix beats a $200 key. I hope this helps other Porsche owners :D .

[70Sixter]

Thanks. Now if you had just specified duct tape and then to wipe the key with WD-40 it would have been the perfect Southern fix. :D

[azzar0]

Brent,

I opened my key to replace the battery, and when I did that the battery went flying and haven't been able to find it. Did I lose anything else or is the battery the only moving part inside the key head?

Thanks!

[brent]

Brent,

I opened my key to replace the battery, and when I did that the battery went flying and haven't been able to find it. Did I lose anything else or is the battery the only moving part inside the key head?

Thanks!

I don't think you lost anything. Just expand the first picture in the thread to see the internal components. When I opened my key I have a circuit board with the battery in one half and the other half holds the key and the code pellet. This pellet is a glass capsule that is the second layer of electronic security to the key and is located in a slot in the lower left quadrant of the plastic key head. The pellet and key fit together securely and takes an effort to get them apart. The circuit board readily snaps loose from the plastic half. So if you have a circuity board, a battery, a glass pellet and the two halves that is it. You could replace the battery and snap it all back together to see if it works.

Edited July 16, 2007 by brent

[azzar0]

I don't think you lost anything. Just expand the first picture in the thread to see the internal components. When I opened my key I have a circuit board with the battery in one half and the other half holds the key and the code pellet. This pellet is a glass capsule that is the second layer of electronic security to the key and is located in a slot in the lower left quadrant of the plastic key head. The pellet and key fit together securely and take an effort to get them apart. The circuit board readily snaps loose from the plastic half. So if you have a circuity board, a battery, a glass pellet and the two halves that is it. You could replace the battery and snap it all back together to see if it works.

Hi Brent,

My car doesn't have a transmitter for remote locks, so the circuit board is missing from my key. What I see is the light bulb on one side, a cilinder looking thingy on the other side (fuse?!?) a contact plate on the bottom, a clear (silicone or glass) circle on top of the contact plate, the black button, and the two halves of the head.

The attached picture is not very clear (cell phone) but should give you an idea.

I will get a battery and see if it works.

Thanks

[brent]

I would not recomment duct tape. The adhesive is likely to gum up the works or at least make a mess over time. The perfect solution would be a simple plastic shim lightly glued in place of exactly the thickness of the gap behind the battery when assembled. Since Gulf Stream, BMW and Mercedes have entered the south, times are changing. Duct tape solutions are becoming endangered species except on Blue Collar TV.

Edited July 16, 2007 by brent

[brent]

I don't think you lost anything. Just expand the first picture in the thread to see the internal components. When I opened my key I have a circuit board with the battery in one half and the other half holds the key and the code pellet. This pellet is a glass capsule that is the second layer of electronic security to the key and is located in a slot in the lower left quadrant of the plastic key head. The pellet and key fit together securely and take an effort to get them apart. The circuit board readily snaps loose from the plastic half. So if you have a circuity board, a battery, a glass pellet and the two halves that is it. You could replace the battery and snap it all back together to see if it works.

Hi Brent,

My car doesn't have a transmitter for remote locks, so the circuit board is missing from my key. What I see is the light bulb on one side, a cilinder looking thingy on the other side (fuse?!?) a contact plate on the bottom, a clear (silicone or glass) circle on top of the contact plate, the black button, and the two halves of the head.

The attached picture is not very clear (cell phone) but should give you an idea.

I will get a battery and see if it works.

Thanks

The cylinder looking thingy is the security pellet, if lost the key will not start the car. It stores a code that is read by the car security systems before it grants permission to start. I am not familiar with your key and can not offer much help.

[RFM]

azzaro

Your car have no remote in the key, only the transmitter is build in. Some German cars, and maybe others, have no remote (earlier types).Some have the remote separately others none.