New PCM with SKIM

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AjRagno

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2005 LJ Auto.

I have a PCM from Wrangler Fix that I’d like to install this weekend. What I haven’t seen discussed is how SKIS is affected. When I brought this up with Mark he said I could leave the module plugged in and the system would continue to function but it would be helpful to hear from those who’ve replaced their PCM.

My understanding is that the PCM will have SKIS enabled but it is not activated unless the ignition is turned on with the SKIM (module) plugged in.

My expectations are that if I leave the SKIM plugged in, SKIS will be activated in the PCM but because the PIN in the module has not been programmed into the PCM, the engine will either shut down or the sentry key icon in the cluster will remain on to indicate a SKIS problem. Also, if I unplug the SKIM, the sentry key icon will remain on because the cluster is no longer receiving communication from the module.

Anyone have any firsthand experience with this when they installed a Wrangler Fix PCM?
 
Since I recently had SKIM added to my '01 and had a few issues along the way; I have experienced first hand some of these problems.
YES .... the yellow circle surrounding a key icon will remain lit during vehicle operation because the cluster talks to the PCM, but isn't receiving communications from the SKIM module. Unplugging the module will have no impact on the icon. You will need to have the security enabled in the PCM and have the PIN available while doing it.

You should contact #MR.BLAINE about this....; he is quite knowledgeable about this topic....
 
AjRagno said:
2005 LJ Auto.

I have a PCM from Wrangler Fix that I’d like to install this weekend. What I haven’t seen discussed is how SKIS is affected. When I brought this up with Mark he said I could leave the module plugged in and the system would continue to function but it would be helpful to hear from those who’ve replaced their PCM.

My understanding is that the PCM will have SKIS enabled but it is not activated unless the ignition is turned on with the SKIM (module) plugged in.

My expectations are that if I leave the SKIM plugged in, SKIS will be activated in the PCM but because the PIN in the module has not been programmed into the PCM, the engine will either shut down or the sentry key icon in the cluster will remain on to indicate a SKIS problem. Also, if I unplug the SKIM, the sentry key icon will remain on because the cluster is no longer receiving communication from the module.

Anyone have any firsthand experience with this when they installed a Wrangler Fix PCM?
Click to expand...

What I believe WranglerFix is doing is allowing the SKIM module to do it's job without registering the SKIM module with the PCM. Meaning, as long as the SKIM module says the key is okay, the PCM is fine with it. If you unplug the SKIM module and try starting with an unchipped key (or breaking the keyed ignition to force it to start), normally the PCM will say that's no good. With the WranglerFix ECU if you unplug the SKIM module the ECU says it's okay and will start the engine.

All this means that if the thief is familiar enough with cars to try unplugging SKIM module and then starting the Jeep (but not familiar enough to know that this normally won't work on Jeeps) they will be able to drive away. Iirc MrBlaine had one that was attempted to be stolen by disconnecting the SKIM module but wasn't able to start it due to the ECU being paired to the SKIM.
 
toximus said:
What I believe WranglerFix is doing is allowing the SKIM module to do it's job without registering the SKIM module with the PCM. Meaning, as long as the SKIM module says the key is okay, the PCM is fine with it. If you unplug the SKIM module and try starting with an unchipped key (or breaking the keyed ignition to force it to start), normally the PCM will say that's no good. With the WranglerFix ECU if you unplug the SKIM module the ECU says it's okay and will start the engine.

All this means that if the thief is familiar enough with cars to try unplugging SKIM module and then starting the Jeep (but not familiar enough to know that this normally won't work on Jeeps) they will be able to drive away. Iirc MrBlaine had one that was attempted to be stolen by disconnecting the SKIM module but wasn't able to start it due to the ECU being paired to the SKIM.
Click to expand...

This is somewhat disappointing - when I asked about this Mark told me it would register after about 20 cycles. But maybe that’s true and just not as into the weeds as you’ve seen and I didn’t know to ask more.

at the end of the day, I guess for me it’s either it runs or not, but may need to add a few security measures.
 
rasband said:
This is somewhat disappointing - when I asked about this Mark told me it would register after about 20 cycles. But maybe that’s true and just not as into the weeds as you’ve seen and I didn’t know to ask more.

at the end of the day, I guess for me it’s either it runs or not, but may need to add a few security measures.
Click to expand...

That could be, I don't know, but would be odd behavior for electronics to be set after 20 cycles for no reason. My understanding, but he hasn't wanted to disclose how they work understandably, is that he's reverse engineering these and using write once memory (like a CD-ROM has) which is cheaper and more durable than rewritable memory (like a USB memory stick has).

You could test if it registers SKIM after 20 cycles by disconnecting the SKIM module and see what happens when you try to start it.
 
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toximus said:
You could test if it registers SKIM after 20 cycles by disconnecting the SKIM module and see what happens when you try to start it.
Click to expand...

Honestly, as long as it works I am pretty happy - it's garaged most the time anyway and there are other ways to set up obfuscations. However I will do that for others that are concerned about that as a feature.
 
I replaced the PCM Friday evening and left the module plugged in. The cluster and bulb check appear to function normally, with the SKIM light illuminating during the bulb check, then turning off. I haven't yet attempted to determine if SKIS is functional.

The case wasn't particularly pretty, but the PCM did solve my issues and I didn't experience any complications.

View attachment 182483
 
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AjRagno said:
I replaced the PCM Friday evening and left the module plugged in. The cluster and bulb check appear to function normally, with the SKIM light illuminating during the bulb check, then turning off. I haven't yet attempted to determine if SKIS is functional.

The case wasn't particularly pretty, but the PCM did solve my issues and I didn't experience any complications.

View attachment 182483
Click to expand...

I removed my SKIM module because I was afraid the Jeep would not recognize new PCM I bought from Wranglerfix and this leave me with my jeep not working. I use it without a module and works fine but adding parts to it makes it more attractive thieves. I do have an alarm system from viper and gps. I get alerts to my phone if something happens. Should I try putting my SKIM back on. I’m kinda scared. I have the original key and some spares I made. And the spares I made I believe have a pin. I’m not sure at all about any of these things but I’d love to have the SKIM back on.
 
Octavio Lizarraga said:
I removed my SKIM module because I was afraid the Jeep would not recognize new PCM I bought from Wranglerfix and this leave me with my jeep not working. I use it without a module and works fine but adding parts to it makes it more attractive thieves. I do have an alarm system from viper and gps. I get alerts to my phone if something happens. Should I try putting my SKIM back on. I’m kinda scared. I have the original key and some spares I made. And the spares I made I believe have a pin. I’m not sure at all about any of these things but I’d love to have the SKIM back on.
Click to expand...

just plug in your skim module and fire up the jeep. On first crank they all marry and the jeep fires up! Please let me know if you need anything.
 
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Wranglerfix said:
just plug in your skim module and fire up the jeep. On first crank they all marry and the jeep fires up! Please let me know if you need anything.
Click to expand...

I can confirm this worked just fine for me and I even added additional keys to the skim afterward without issue (and tested a non-married key where the jeep shut off - just don't do that test more than once).
 
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I appreciate it @Wranglerfix @macleanflood @rasband I’m going to pop that skim back in and give it a go. The spares are made from a locksmith and not by the dealer. I’ll confirm back when I plug it in.

*Side note: the spares are not from the dealer. I got them made from a locksmith with the previous PCM and SKIM installed.
Wranglerfix said:
just plug in your skim module and fire up the jeep. On first crank they all marry and the jeep fires up! Please let me know if you need anything.
Click to expand...
just plug in your skim module and fire up the jeep. On first crank they all marry and the jeep fires up! Please let me know if you need anything
 
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Reactions: Wranglerfix and macleanflood
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