When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
Battery was dying... would not open the trunk... had to get close to unlock the door. OK, in replacing the battery, I decided to get out a bottle of alcohol and some Q-tips and clean all the contacts. I don't know how crud gets in there but it does.
So with my nerd (or is it geek?) Opti Visor Magnifier I see this little chicklet with no electrical connections:
How does this thing work? How does this work with no power supply?
The short answer is the power comes from an external antenna; a signal is beamed "to" the transponder, and it emits a coded signal "back" to the external system.
Battery was dying... would not open the trunk... had to get close to unlock the door. OK, in replacing the battery, I decided to get out a bottle of alcohol and some Q-tips and clean all the contacts. I don't know how crud gets in there but it does.
So with my nerd (or is it geek?) Opti Visor Magnifier I see this little chicklet with no electrical connections:
How does this thing work? How does this work with no power supply?
Peace
Bruce in Philly
See the chicklet security module below at about the 7-8 o'clock position in the battery cavity:
The little "pill" in your keyfob is officially called an RFID and is energized by the car's transmitter. When the car sends out a RF signal, it energizes the RFID and returns an encrypted rolling code that only your car's ECU/security module can decode. Once they complete a successful handshake, the ECU tells the car it's ok to start. Does the process pretty quick too. lol
Check this thread out from Skip (i.e. Porschetech3). Skip was a Porsche Gold Meister Technician before retiring at 40 years in the automotive service industry.
The little "pill" in your keyfob is officially called an RFID and is energized by the car's transmitter. When the car sends out a RF signal, it energizes the RFID and returns an encrypted rolling code that only your car's ECU/security module can decode. Once they complete a successful handshake, the ECU tells the car it's ok to start. Does the process pretty quick too. lol
So, how does anyone steal these cars without the key that has the coded RFID chip, as I know they get stolen, like the one in New Mexico or Vegas (can't remember which).
So, how does anyone steal these cars without the key that has the coded RFID chip, as I know they get stolen, like the one in New Mexico or Vegas (can't remember which).
You would go on e-bay and buy a matched set/programmed DME/Immobilizer/ key,(about $500) use a slidehammer to yank the ignition lock out, unlock the steering and plug up the DME and Immobilizer, using the matched key to immobilizer antenna, start the car and drive it off.
OR you just use a rollback to drag the car up on it with the tow hook and drive off, then take your time with the electrical swap.
Not that I know anyone who has done this or have done it myself, but that's how it could be done.
You would go on e-bay and buy a matched set/programmed DME/Immobilizer/ key,(about $500) use a slidehammer to yank the ignition lock out, unlock the steering and plug up the DME and Immobilizer, using the matched key to immobilizer antenna, start the car and drive it off.
OR you just use a rollback to drag the car up on it with the tow hook and drive off, then take your time with the electrical swap.
Not that I know anyone who has done this or have done it myself, but that's how it could be done.
Isn't the DME in the back under the Bose subwoofer. Isn't that what I had to access for the twisted pair of wires to connect the 3axis accelerometer to for my DSC controller to work or can this somehow be circumvented at the front once the ignition switch is disconnected?
Isn't the DME in the back under the Bose subwoofer. Isn't that what I had to access for the twisted pair of wires to connect the 3axis accelerometer to for my DSC controller to work or can this somehow be circumvented at the front once the ignition switch is disconnected?
Yep, if you don't have Bose, you just grab the carpet/foam and pull it out exposing the DME and other electronics.
10-20-2020, 06:49 PM
Key Transponder - Questions for RF Engineers
