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For those with a 2015 SS with the manual transmission, you have probably learned about CAGS, the system that under certain circumstances prevents the shift lever moving directly from 1st to 2nd in order to save you from the gas guzzler tax.

This thread is not to debate the advantages or disadvantages of CAGS, that has been handled in other threads already. This one is intended to identify precisely where some essential components of that system reside.

First of all, there are computers that monitor RPM, throttle position, speed, etc. I don't know where they are, they're in the car somewhere. There are multiple solenoids that are located within the transmission housing. One of them is energized for CAGS, and the other is energized for reverse.

If one crawls under the driver's side of the 2015 SS and looks straight up, you'll find something that looks like picture 1.
cags1.jpg
The red line is scrawled on the lowest part of the 6-speed manual transmission housing, which is a rib or fin that is closest to the ground. Visible in the picture is most of the left (driver's) side of the side and the bottom of the transmission. The green arrow points along a seam in the housing, in the direction of up into the cabin. You'll notice a connector that is very easy to reach. That is not the connector for CAGS.

cags2.jpg
Picture 2 shows the same general area from a bit closer to the engine, looking backwards along the length of the transmission. The very convenient connector is for the reverse solenoid. There is another connector, higher and much harder to reach and pretty close to the heat shield. That second one is for CAGS.

cags3.jpg
Picture 3 shows that when you look straight up, there is a metal tab or lug on the side of the transmission housing that hides the CAGS connector pretty well.

If a bit of spinning and bouncing road debris hits the exposed wiring loom just right, the loom could theoretically snag on the lug temporarily, thus more obviously revealing the CAGS connector, as shown in Picture 4.
cags4.jpg
Note that the CAGS connector is held in place by a plastic tab that engages with the socket in the transmission housing.

This same retention is used on the reverse solenoid, and in fact they both use the same connector. The connector itself has a multi-ribbed weather-resistant seal to prevent water and other contaminants from fouling the electrical connections. The same connectors are used on the SLP 21008 loom-extending device.

You would never want to operate your 2015 SS with this connector unplugged because it would prevent the CAGS system from operating. Since this is such an important function, the car has been designed to monitor this connection to ensure that the circuit is never unplugged. If the vehicle were to be operated while the CAGS connection was unplugged, it would probably log trouble codes and likely warn you to have the vehicle serviced.

Should your car suffer the extremely unlikely event of this connector becoming spontaneously detached from the transmission housing, you should certainly take it to the dealer and have them plug it back in for you, because access to this connector is very difficult and narrow and the factory wiring loom just barely reaches.

Under no circumstances should you install an SLP 21008 loom extender at this location. Although the SLP 21008 connectors perfectly match the CAGS connectors and have the same weather seals and the whole unit adds about three inches of slack for the factory loom, there is a problem with the SLP 21008. Even though the electrical connectors match perfectly, the SLP 21008 loom extender appears to have some circuitry inside that prevents the CAGS system from operating correctly, in a way undetectable by the computers in the car. The car will still generate the display in the driver's information center warning you to shift from 1st to 4th to save gas, but the CAGS solenoid will not engage and it will be possible to shift from 1st to 2nd under any and all combinations of throttle position, RPM, and vehicle speed. If you use this product, you may be at risk of wasting gas.
 

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You should also never tune your car because it adds extra horsepower, which causes a heavier foot on the gas pedal, which causes excessive gasoline consumption, which puts a big a$z smile on your face...
 

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You should also never tune your car because it adds extra horsepower, which causes a heavier foot on the gas pedal, which causes excessive gasoline consumption, which puts a big a$z smile on your face...
I think it would be easier to just not buy an SS....get a prius and hug trees and drink water that costs $6 a bottle
 

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I think it would be easier to just not buy an SS....get a prius and hug trees and drink water that costs $6 a bottle
LOL - that's so true...
 
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Thanks LAG!

I was hoping someone would post some SS photos showing the connectors before I got my SS. Now I can install an Apex 8001...er I mean review how to maintain the MPG saving factory CAGS connections. Great work!
 

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Wonder if it would be possible to post a photo of the offending part SLP 21008, and maybe a photo of a simulated installation of said loom extender. This would be extremely helpful if I were ever to consider purchase of a previously owned SS. I would want to verify that the vehicle was not being abused in such a manner before making a purchase.

Edit:
Here's a link to an illustrated instruction sheet from SLP. The photos may not be exactly the same transmission but you can get the general idea. Shame on them for causing so many dinosaurs to lose their peaceful rest for eternity!
http://www.slponline.com/instructions/21008.pdf

Many thanks to LAG for the annotated photos of actual transmission & connectors!
 

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Discussion Starter #7
Wonder if it would be possible to post a photo of the offending part SLP 21008, and maybe a photo of a simulated installation of said loom extender. This would be extremely helpful if I were ever to consider purchase of a previously owned SS. I would want to verify that the vehicle was not being abused in such a manner before making a purchase.
If you found a previously owned SS and wanted to check for the offending part, you'd have to realize that somebody who installed one might sort of interweave it into the existing loom to keep it from touching either the heatshield or the metal case of the transmission. Such a type of installation weaving it into the existing wires would make it really hard to identify the presence of an SLP 21008 after it is installed.

cags6.jpg

(The above simulated installation is unfortunately somewhat out of focus, which is why I didn't originally post it.)

Muzzys on Amazon has nice detailed pictures of the SLP 21008 you'd be looking for in the previously owned SS. As of this writing, they also offer free shipping, should you wish to get one for direct visual comparison, and I have personal experience... err, on something else maybe... that they ship promptly.
 

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Very informative. I will not install the SLP 21008 lest I run the risk of fooling my car's computational facilities and of excessive burning of precious non-renewable fuel. And I will definitely not order one from Muzzys on Amazon since their prompt and free shipping jeopardizes the free-market economy as it stands today.
 

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You guys are to much. Lets see how fast the above said offending part ships when ordered on a sunday night
 

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You guys are to much. Lets see how fast the above said offending part ships when ordered on a sunday night
Hypothetically, such a part ordered from Muzzys the night of Sunday May 3 would have been delivered Wednesday May 6, demonstrating impressively speedy shipping. Pure speculation, of course.
 

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Hypothetically, such a part ordered from Muzzys the night of Sunday May 3 would have been delivered Wednesday May 6, demonstrating impressively speedy shipping. Pure speculation, of course.
Got said part today thanks to the USPS.
 
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Under no circumstances should you install an SLP 21008 loom extender at this location. Although the SLP 21008 connectors perfectly match the CAGS connectors and have the same weather seals and the whole unit adds about three inches of slack for the factory loom, there is a problem with the SLP 21008. Even though the electrical connectors match perfectly, the SLP 21008 loom extender appears to have some circuitry inside that prevents the CAGS system from operating correctly, in a way undetectable by the computers in the car. The car will still generate the display in the driver's information center warning you to shift from 1st to 4th to save gas, but the CAGS solenoid will not engage and it will be possible to shift from 1st to 2nd under any and all combinations of throttle position, RPM, and vehicle speed. If you use this product, you may be at risk of wasting gas.
The SLP CAGS harnesses or "skip shift eliminators" for 4th Gen Fbodys were the same way. The skip shift light would still come under however, you were not locked out of any gears. It is not a defect, it is just simply the way it is engineered. Honestly I like this way. You get a warning that lets you know when you have an opportunity to save some fuel but still have complete control of the vehicle. Even thought I have this type of setup on my firehawk I still frequently skip gears when just cruising. no reason to row all 6 in low speed traffic when I can use 3 or 4 of them and save my left knee a little pain. A person can turn CAGS off in the computer if they are using an aftermarket tune so If you dont want the light or just dont want to use a harness all together then get with your tuner and have them turn the system off completely. Hope this helps.
 

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The SLP CAGS harnesses or "skip shift eliminators" for 4th Gen Fbodys were the same way. The skip shift light would still come under however, you were not locked out of any gears. It is not a defect, it is just simply the way it is engineered. Honestly I like this way. You get a warning that lets you know when you have an opportunity to save some fuel but still have complete control of the vehicle. Even thought I have this type of setup on my firehawk I still frequently skip gears when just cruising. no reason to row all 6 in low speed traffic when I can use 3 or 4 of them and save my left knee a little pain. A person can turn CAGS off in the computer if they are using an aftermarket tune so If you dont want the light or just dont want to use a harness all together then get with your tuner and have them turn the system off completely. Hope this helps.
I for one don't want to tune the car. Only mods added are easily removed for any dealer services or needed visits.
 
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My point is that you don't have to tune it. Never in my post did I once say that tuning was a requirement. Tuning only turns off the in dash skip shift warning. The harness works either way but you still get the warning on the dash cluster telling you when to skip gears it just doesn't lock you out of the gears.
 
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Also my Gen 1 V had the SLP CAGS harness and it alerted you on the dash when to "skip shift" but did not lock you out of gears.
 
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Discussion Starter #20
The SLP CAGS harnesses or "skip shift eliminators" for 4th Gen Fbodys were the same way. The skip shift light would still come under however, you were not locked out of any gears. It is not a defect, it is just simply the way it is engineered.
Okay... my earlier comment was perhaps too much tongue-in-cheek. There is nothing wrong with Muzzy's fine product, it works precisely as it is designed to do, preventing the CAGS solenoid from engaging without the computers in the car being able to see that happening.

Since the computers think CAGS is still operating normally, of course they still make the same display in the dash, which I agree is trivial to ignore.

If, on the other hand, you didn't want to admit publicly you installed a warranty-voiding "skip-shift eliminator", you might instead describe it a "loom extender". :wink:
 
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