Gentlemen - The original question still remains unanswered. See "Red Dog's" original question about the chips in his first posting on this subject. Does anyone have an answer for him, or the rest of us?

Someone else asked I believe it was CL770, in reply # 8, if anyone has used the new transponder chips listed on ebay and the tool that is also listed for programming them. I can't see that anyone answered that question either. Does anyone have an answer?

I'm not being super critical, just wondering if anyone has any answer's to these questions.

Jim





































"

 

I listed this information because this is what I use and it works fine for me!

I'm also looking at the SKREEM modules with another forum member and I'd like to know from someone who has had a SKREEM failure if the no start issue effects all the keys for the car or just one key? If someone can tell me this it would narrow the failure down a bit.

 

CL770 - Thanks. That's what I wanted to know - if someone used this combination and if it worked.

Thanks,

Jim

 

I have seen several references to RFID chip readers/writers and would like to know which one works. If so I'll buy one and read my transponders and see if I can determine a pattern.

 

I thought it was made clear YEARS ago, when the SKREEM fails, neither key (well for those with more than one key) works.
There have been many failures and both keys fail to start the car.

 

 

180 - Very good question about boards being universal and why not. I agree with you that if these circuit boards are VIN sensitive, that would be "overkill". Any way we can find out? My understanding, right or wrong, is that the boards are for locking and unlocking and for the panic alarm, and that the chip is for starting the car. I thought the circuit board was to send a signal to the chip, to the SKREEM and then allowed the ignition to start the car.

Jim

 

Hi Jim, the circuit board is ONLY for the lock/unlock/panic. The TRANSPONDER in the FOB is to allow the ring to pick up signal and allow the car to start through the SKREEM.

.

 

Want to see if the circuit board is universal?Go to a buddy's Crossfire and double click YOUR fob, then have him turn on the ignition with HIS key fob.
Then, try to lock/unlock the doors with YOUR fob; if it works, it is a universal circuit board.
(Don't forget to reprogram his SKREEM to match his fob after the test)
This test would be like reprogramming the SKREEM to match the fob after a battery disconnect.
If someone tries this test let us know the results.
Would try this myself if another Crossfire was available.
The transponder chip in the fob is another matter to deal with.
Cheers,

 

 

Chooch - 180 - Hope there is an easier way to find out if they are universal. I don't have a friend with a Crossfire, so that rules me out. I hope someone on the forum has a way find out the answer. I wouldn't want to mess up ANYONE's SKREEM module. Maybe someone that has two Crossfire's in their family.

Jim

 

jafaryj - Can you help us out on this question? I'll send you an email.

Jim

 

C'mon you guys. The FOB board is NOT VIN-specific, and we all know that - you can buy generic FOBs off eBay, transplant the RFID chip and the blade from the old FOB, insert it, hit a button twice - and you are good to go.

We have all known this for YEARS.

And even if you didn't already know this - "rolling code" would be your first clue that the FOB board is generic.

 

Dammit,Dave. You know this **** better than THAT!

Is it capable of transmitting and receiving signals at a distance or does it receive only when in close proximity to the halo.
Not the Halo - close proximity to the antenna, behind the Speedometer/Tachometer.

Its in the service manual diagrams, look under "wiring" then "Connector pinouts".

• The HALO is used to energize and communicate with the RFID chip. (Pins 1 and 2 of C3 on the SKREEM are the 'hot' and 'shield' going to the Halo, shielded coax is used to prevent the signal from radiating outside the ring, more on that below.)
• The rolling code lock/unlock board communicates with the SKREEM with the antenna wire in the harness of the SKREEM. (Pin 6 of C1 [C1 is the main SKREEM connector, that dead-end wire on pin 6 is the antenna.])

Some RF basics here:
The halo is not so much an antenna but a coil.

Antennas are intended to radiate. And the antenna on the SKREEM does that, it also is capable of intercepting signals - and it does that, too. When you press a button, your FOB transmits, the SKREEM hears it and IT transmits back, "rolling the code" in the FOB.

The "halo" (coil) is intended to radiate RF energy as well, but it is designed to contain that radiation largely in the area inside it's circumference. This is for two reasons:

1. We need a considerable amount of energy directed to the RFID chip, we need this because this RF is the ONLY source of power for the RFID chip to use to transmit back. When the RFID chip receives this power, it uses it to generate it's signal with the secret code the SKREEM is looking for. So we contain the RF in that small area it is needed in.
2. We do not want the signal from the SKREEM or the response from the RFID chip to be detectable to anyone trying to listen to record the code, that would defeat the purpose of the RFID chip in the first place. So again, we use a coil to contain the signal.

This is why there are two "antennas" - each is designed for a specific purpose.

35 years in RF (radio) here. The things I do not know could fill volumes of books - but I better know RF by now.

 

Although I know you are aware, the following is reiterated for others reading this post .
Originally the main purpose of this thread was to address the key fob transponder chips, but it expanded to cover the fob's Remote Keyless Entry (RKE) transmitter circuit board function with regard to controlling the central locking system.
The fob's RKE circuit board must be synchronized with the SKREEM using a rolling code to lock/unlock doors or set panic alarm.

• The key does not have to be in the ignition switch for the fob circuit board to transmit to the SKREEM. It communicates at distance via RF signal when the lock/unlock buttons are pressed.
• To resynchronize the SKREEM's lock/unlock function with the RKE transmitter circuit board:

1. Press one of the fob buttons momentarily twice.
2. Then turn the key in the ignition switch to the ON/RUN position within 30 seconds.

• Turning the ignition switch to ON/RUN powers up the SKREEM's antenna to query the key's chip for validity.
• With a valid chip in the antenna ring, the SKREEM synchronizes with the last RKE transmitter code received in the past 30 second

So, it should not matter which RKE transmitter was activated as long as the valid transponder was in the antenna ring when the key was turned to ON/RUN.

Or, I missed something along the line ... thoughts?

 

You got it!

There are TWO ways of syncing the FOB.

• Your way.
• The owner's manual way: Put the key in the ignition, turn to "ON" and hit either button twice.

I know the owner's manual way works cause I've had to do it quite a few times in nine years and three cars.
I do remember reading about your way - that comes from the student reference, doesn't it?

 

I do not think this is correct at all.

 

Although the student reference is one of the many pubs I've recently read, most of the text was from the Service Manual.
It's hard trying to nail down what is actually going on with the RKE, SKREEM, PCM, BCM, and Central Locking System.
They are all interrelated to some extent and not much documentation.
Also, along the reading, I found that the FOB RKE has a range of 20 meters (66 feet), that's a pretty good distance from the halo.
But I don't think the halo is the RKE's receive antenna.
When I replaced my SKREEM, there was a second 2-wire connector next to the halo connector that looked like its twin. I'm betting that the leads went to the RKE receive antenna.
Wish I had traced it out when I had the dash out...

BTW: Although I'm a newbie (got my Crossfire in SEP '18), I did spend quite a few years as a Systems Engineer and Software Engineer before turning Educator (Not much software work in Pensacola, but a lot of Training/Education opportunities and there is the sugar white sands at the beach.)
Also, wish 35 years in radio under your belt I'll bet you know the world of Pentodes, Triodes, Diodes and solid state components (Npn, pnp) etc. that I started out with.
HAM License KR4BY

Are we having fun, yet?

 

I DID read about that technique somewhere.
But I KNOW the owne'rs manual way works.

 

Ex WN8VUX, Ex WB8BUX, currently WR8Y.

Have not been active in over ten years. I do P25, NXDN and DMR all day long at work.

I do miss CW contesting on HF, tho.