Transponder ignition

[Paulstanfill85]

My 2003 has a transponder ignition. My lock cylinder is worn out and ignition switch showing signs of near death.

Question is this:

Does the jeep store the transponder ID in the ignition switch opposite the lock cylinder, or does it store it elsewhere? Can I swap the switch, actuator, and key a lock to my key and start the vehicle or will it expect a different ID?

Thanks!

 

[CharlesHS]

IF I understand correctly... the SKIM module at the ignition is paired to the key(s) and the PCM and module are paired.
A new ignition key tumbler can be installed, but it needs to be keyed to the existing gray keys otherwise the Jeep will need to be brought to the dealership OR someone with the knowledge to reprogram....
It is my understanding the grey keys can only be programmed once to a module.

 

[L J]

Does the jeep store the transponder ID in the ignition switch opposite the lock cylinder, or does it store it elsewhere?

The SKIM module is independent of the cylinder, actuator and ignition switch.

Can I swap the switch, actuator, and key a lock to my key and start the vehicle or will it expect a different ID?

Thanks!

Yes, just unclip the module to move it if needed but don't unplug it.

 

[Irun]

I just went through this. If you only need the cylinder, get one of these. The SKIM module, key, and computer are paired. The lock cylinder will worked with either SKIM or non-SKIM. The one below allows you to code your existing key to the new cylinder very easily.

https://www.amazon.com/dp/B07D8BKR5M/?tag=wranglerorg-20

 

[mrblaine]

My 2003 has a transponder ignition. My lock cylinder is worn out and ignition switch showing signs of near death.

Question is this:

Does the jeep store the transponder ID in the ignition switch opposite the lock cylinder, or does it store it elsewhere? Can I swap the switch, actuator, and key a lock to my key and start the vehicle or will it expect a different ID?

Thanks!

Do not key the existing lock cylinder to your existing key unless it is a spare that has little use. Get a new key cut by a dealer to the VIN using their code cutting machine. That will give you one perfect key to re-key the ignition cylinder. Use that good key to get other keys cut with the key machines at stores and locksmiths.

As stated, you don't have a transponder ignition. You have transponder keys that are picked up by the antenna ring around the key lock part of the ignition switch. That antenna goes to the SKIM module which uses the key coded info to allow the vehicle to stay running after it is started.

 

[AjRagno]

I did not have a positive experience with Dorman 924-784.

I was having an issue with my ‘05 LJ where the gauges and fuel pump would not activate with the key in the on position. This turned out to be a PCM issue but along the way I did also replace the ignition lock cylinder.

My Jeep came with 3 Jeep keys so I keyed the Dorman lock cylinder with an unused key. Around 6 moths later the cylinder started to feel rough as I turned the from off to on. Then one day SKIS light continued flashing after the engine started. I don’t recall the code but it indicated that the engine was started before the RF code could be read. Within a few days, the key stopped being recognized and the system activated and shut the engine down. None of the 3 keys worked at this point. I ended up putting the original ignition lock cylinder back in. The lock cylinder does have something to do with the SKIS, likely related to the ignition sense circuit.

Dorman is the simplest solution, but I would recommend keeping your original lock cylinder in your Jeep.

 

[mrblaine]

I did not have a positive experience with Dorman 924-784.

I was having an issue with my ‘05 LJ where the gauges and fuel pump would not activate with the key in the on position. This turned out to be a PCM issue but along the way I did also replace the ignition lock cylinder.

My Jeep came with 3 Jeep keys so I keyed the Dorman lock cylinder with an unused key. Around 6 moths later the cylinder started to feel rough as I turned the from off to on. Then one day SKIS light continued flashing after the engine started. I don’t recall the code but it indicated that the engine was started before the RF code could be read. Within a few days, the key stopped being recognized and the system activated and shut the engine down. None of the 3 keys worked at this point. I ended up putting the original ignition lock cylinder back in. The lock cylinder does have something to do with the SKIS, likely related to the ignition sense circuit.

Dorman is the simplest solution, but I would recommend keeping your original lock cylinder in your Jeep.

No, the ignition lock cylinder has zero to do with reading the chip in the key. There is not an ignition sense circuit. Not sure what you have going on but it has nothing to do with the lock cylinder.

In fact, we use a random blank lock cylinder and uncut keys every time we do a SKIM set up. We do that so we don't cut keys that won't program.

To clarify, we grab a random lock cylinder, we unpin it, put random customer supplied uncut keys it in, plug that into a random year range vehicle so we can program the SKIM and pair that to the customer supplied PCM in a vehicle it is not going to be installed in, and then we put it all back together and ship off the programmed and paired stuff after we cut the keys. It has never not worked.

 

[Paulstanfill85]

Perfect fellas. I appreciate the information a bunch!

 

[AjRagno]

No, the ignition lock cylinder has zero to do with reading the chip in the key. There is not an ignition sense circuit. Not sure what you have going on but it has nothing to do with the lock cylinder.

In fact, we use a random blank lock cylinder and uncut keys every time we do a SKIM set up. We do that so we don't cut keys that won't program.

To clarify, we grab a random lock cylinder, we unpin it, put random customer supplied uncut keys it in, plug that into a random year range vehicle so we can program the SKIM and pair that to the customer supplied PCM in a vehicle it is not going to be installed in, and then we put it all back together and ship off the programmed and paired stuff after we cut the keys. It has never not worked.

There is some correlation with the ignition lock cylinder and the SKIS. If the only part that changed was the functionality of the ignition lock cylinder, then it clearly does have an affect.

 

[L J]

There is some correlation with the ignition lock cylinder and the SKIS. If the only part that changed was the functionality of the ignition lock cylinder, then it clearly does have an affect.

Where is the electrical connection between the lock cylinder and the SKIM, the actuator or the ignition switch that would allow such an effect?

 

[mrblaine]

There is some correlation with the ignition lock cylinder and the SKIS. If the only part that changed was the functionality of the ignition lock cylinder, then it clearly does have an affect.

Again, I do not know what you have going on but it is not the ignition lock cylinder or the efficacy thereof. That is a 100% mechanical connection with exactly zero electrical interface whatsoever. All the ignition lock cylinder does is turn an actuator that goes to the actual electrical ignition switch located on the left side of the column.
There are no electrical connections, circuity, proximity sensor, etc. that have anything at all to do with the ignition lock cylinder. It is simply mechanical, nothing more.

 

[mrblaine]

Where is the electrical connection between the lock cylinder and the SKIM, the actuator or the ignition switch that would allow such an effect?

It doesn't exist and you can easily prove that by pulling it and turning the ignition switch with a screwdriver which will activate all the ACC, Run, Start functions that you see with the key based on position.

 

[Paulstanfill85]

It doesn't exist and you can easily prove that by pulling it and turning the ignition switch with a screwdriver which will activate all the ACC, Run, Start functions that you see with the key based on position.

So, quick question. Because I agree with you 100%.

I replaced the ignition, cylinder, and actuator. The jeep starts and then dies with the transponder light blinking as though it doesn't recognize my key. I didn't mess with the skim module at all. I'll go grab my original keys and find out if any work currently.

 

[mrblaine]

So, quick question. Because I agree with you 100%.

I replaced the ignition, cylinder, and actuator. The jeep starts and then dies with the transponder light blinking as though it doesn't recognize my key. I didn't mess with the skim module at all. I'll go grab my original keys and find out if any work currently.

Read that like someone wrote it to you and see (a) where the question is, (b) if it makes any sense with the lack of info. What key did it not recognize and why are the original keys different?

 

[Paulstanfill85]

Read that like someone wrote it to you and see (a) where the question is, (b) if it makes any sense with the lack of info. What key did it not recognize and why are the original keys different?

Little update. It spontaneously forgot my 3rd key somehow. Wild. Other keys work.

False alarm.

 

[Paulstanfill85]

Read that like someone wrote it to you and see (a) where the question is, (b) if it makes any sense with the lack of info. What key did it not recognize and why are the original keys different?

Bad post. I was frazzled.

The same key used to pull the jeep in the shop would not start it afterward. The key sentry light blinks when it is inserted and turned.

I don't know why a key that worked for three years didn't work today after the install. The original two keys work but the third I made and had been using does not anymore.

 

[mrblaine]

Bad post. I was frazzled.

The same key used to pull the jeep in the shop would not start it afterward. The key sentry light blinks when it is inserted and turned.

I don't know why a key that worked for three years didn't work today after the install. The original two keys work but the third I made and had been using does not anymore.

Reprogram it and see if that fixes it.

 

[ger0]

Bad post. I was frazzled.

The same key used to pull the jeep in the shop would not start it afterward. The key sentry light blinks when it is inserted and turned.

I don't know why a key that worked for three years didn't work today after the install. The original two keys work but the third I made and had been using does not anymore.

I know this post is a couple of years old. I have experienced exactly what Paulstanfill85 did. I found that the original lock will recognize all 3 keys, but the new Dorman unit will only recognize the two keys I usually carry in my pocket. I tested it twice with two different Dorman units both act the same. I decided to put the old ignition lock back in tho it is a little worn from 90k+ of stops and starts. I did talk to the tech support at Dorman twice and they were baffled too and stated that they had not seen this even once either on Jeep or Dodge. At any rate, there must be something about the composition of the materials in the lock cylinder that interfere with the skim system recognizing the third key. My next move is to order a genuine part and see what happens. Btw I posted this to back up the OP's claims, I know some on here doubted what he was saying. When I reach a conclusion I will again post the result.