No, sorry, C11 is an input. While I had the device it was connected to correct, I had the pins backwards. The EBTCM is connected to the Cruise Control Cutoff Relay. When the relay is triggered (by the EBTCM), it opens the contact that sends voltage to the Cruise Control Disengage Input on the Cruise Control computer (removing +12V from this input disengages the computer), as well as closing the contact that sends voltage to C11 on the PCM and the "ASR ACTIVE" light on the Driver's Information Center. My Bosch ABS/ASR manual says that this input is for automatic transmission vehicles only, so it may not be used on manual transmission cars. If I had to guess I'd say it's to switch the PCM from the Cruise shift map back to the Normal shift map when ASR cuts off the cruise control.
On "ice mode," yes, I'm very familiar with it. Chances are your service manual will not tell you anything about it. I know mine don't. For Bosch systems, I do have the actual Bosch book that they wrote about it. Basically, the computer looks at all of its inputs and tries to figure out of the braking force experienced is exceeding the maximum potential threshold of braking for a conventional surface (negative speed delta exceeds set point). If this happens, it assumes that the wheel(s) in question must have come into contact with a low-mu surface (such as ice), and will prevent excessive brake pressure from reaching the calipers. This hopefully allows the wheel(s) in question to resume spinning, returning some level of control to the driver. However, a problem occurs in racing environments where it's entirely possible to have braking equipment and a road surface so good that your braking exceeds that same set point, causing the ABS to think you're on ice, and thus restricting your braking. It's counterintuitive, but if you release the brake pedal momentarily, you 'reset' this input, allowing you to hit the pedal again and should get full braking pressure back. This system is designed and required for all vehicles registered for public roadway use in the US (and probably elsewhere). It is also mandated that the driver should not be able to disable it. This is why dedicated race vehicles tend to use aftermarket ABS which do not have these "nanny" subroutines programmed. Bosch themselves, for example, offer a race-only ABS that does not have any "ice mode" shenanigans.
That said, I can only speak for how Bosch systems work, and it looks like F-Body cars don't use Bosch systems. On a Bosch system, there is a lateral accelerometer linked into the ABS that measures how "hard" you are cornering. On these vehicles, most of the "ice mode" incidents happen in straight-line braking. I was already developing an aftermarket G-sensor for 94-96 Y-Body cars, but after reading up on "ice mode" woes, I believe I can counteract it with the very same sensor. Essentially, giving it a "race mode" that sends false high lateral G-load data to the ABS during straight-line braking, thus convincing the ABS that it cannot possibly use "ice" logic since it's impossible to have such high lateral G-loads on ice. I have not yet tested this system, but according to Bosch's ABS operational theory, it should work.
EDIT:
So I discovered the discrepancy between the usage of pin B22 between what is marked on page 13 of this thread and what's marked in my FSMs. It turns out that it is in fact a difference between vehicles. The F-Body does not use this pin (apparently). The Y-Body uses this pin as "Cruise Control Active," which assumedly is what tells the PCM to use the cruise shift map (which the 4L60E manual claims 'delays the 3->4 upshift and TCC apply during heavy throttle', but the cruise maps for upshifts, downshifts, and TCC apply/release appear to be identical to the normal maps on my Y-body calibrations). However, the B-Body uses pin B22 as a connection to a TCC Temperature Switch located in the feed line to the transmission cooler that connects this pin to ground when the fluid temperature is over 325F. Additionally, the B-Body calibrations have radically different "Cruise Mode" maps compared to Normal Mode maps. The B-Body also has no "cruise control active" input.
This leads me to believe that, in fact, the input itself is used the same way--the input triggers the PCM to switch to the "Cruise" map. But the B-Body has populated its "cruise" map with "hot" values, essentially using the cruise map to account for overheated transmission fluid. Why it does this even though the PCM already has a "hot" map and the B-Body has a transmission fluid sensor input on pin D28 is beyond me.
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