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Controlling the GT350 Exhaust Valve

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In the V6L
Tried a new switch and still getting the same results.

Switch on. All is good and all works fine. Turn switch off and car throws "drive mode not selectable" within about 3-5 seconds.

According to my voltmeter pin 2 on connector C215 carries a constant 12 volt signal back to the two exhaust valves. My understanding is that the PCM then sends a signal to the valves down the violet wires and through pin 34 at connector C212 and C213 in the same passenger footwell. The only other wire we see in the provided diagram is the ground wire at the actual valves themselves. Is it possible that the PCM is monitoring that 12 volt feed into the exhaust valves somehow? It must be if the wiring above is accurate. Does anyone else have 2018 specific GT350 wiring schematics for the PCM or exhaust valves?

Maybe on the 2018 I need to bypass the solenoids completely and run a jumper wire all the way to the grounds to keep the system happy? It's been a while since I've read wiring schematics and these newer can-bus systems are more complicated than what I'm used to. Would like to get some feedback before I try some shiznit and start popping fuses, relays, and god knows what else. At this point I'd just buy the AWE system, but I'm not 100% confident it will work and the price is now up over $350.

View attachment 81290
If you connect a wire from the 12v feed to the ground, you'll just blow the fuse. Not helpful. Can you get a meter on the EXHVAL signal from the ECU? I think C212 and C213 are in the passenger footwell somewhere. I'm guessing EXHVAL is at around 12v when the valves are closed and 0v when they're open. Is this right, or is it the other way around, or is it something else entirely? By the way, it's all just volts and amps, there's no CAN bus involved in this part of the system.

Update: another thing to check in your service manual, which seems to be a little different than mine (later, I guess) is the error codes for problems with the exhaust valves. That may tell you exactly how it works - the whole section is missing from my 2016 manual, but I'd expect it's in your later one.
 
If you connect a wire from the 12v feed to the ground, you'll just blow the fuse. Not helpful. Can you get a meter on the EXHVAL signal from the ECU? I think C212 and C213 are in the passenger footwell somewhere. I'm guessing EXHVAL is at around 12v when the valves are closed and 0v when they're open. Is this right, or is it the other way around, or is it something else entirely? By the way, it's all just volts and amps, there's no CAN bus involved in this part of the system.

Update: another thing to check in your service manual, which seems to be a little different than mine (later, I guess) is the error codes for problems with the exhaust valves. That may tell you exactly how it works - the whole section is missing from my 2016 manual, but I'd expect it's in your later one.
Working to determine exactly which plugs are 212 and 213 right now as I'm working off of the original post's screenshot and don't have the 2018 manuals myself. May have to at least buy the $80 wiring schematic manual to figure this out. Will locate those harnesses, test, and report back.
 
1,246
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In the V6L
Working to determine exactly which plugs are 212 and 213 right now as I'm working off of the original post's screenshot and don't have the 2018 manuals myself. May have to at least buy the $80 wiring schematic manual to figure this out. Will locate those harnesses, test, and report back.
This might be more cost effective: https://www.motorcraftservice.com/Purchase/ViewProduct

The factory stuff for all model years and three days use for $22 or so.
 
Baby steps.

Hooked up Forscan and data logged the sensor. Apparently the 2018 has an exhaust valve status tattle tale signal coming in. You can see in thr attached image on the top line that I close the exhaust valve and it moves from 100% to 0% on the exhaust valve line. On the status you see all is good. With a 0 value. I then toggle the switch which causes a temporary spike too 100 but. At this point there's no issue and the value returns to 0. Seconds later though the system jumps to a low value and holds that value. This is where the car indicates a fault and the drive mode selection and all other faults originate. I then disable the interruptor switch and the value returns to 0 and drive modes are reenabled.

20221216_203620.jpg
 
1,246
1,243
In the V6L
Baby steps.

Hooked up Forscan and data logged the sensor. Apparently the 2018 has an exhaust valve status tattle tale signal coming in. You can see in thr attached image on the top line that I close the exhaust valve and it moves from 100% to 0% on the exhaust valve line. On the status you see all is good. With a 0 value. I then toggle the switch which causes a temporary spike too 100 but. At this point there's no issue and the value returns to 0. Seconds later though the system jumps to a low value and holds that value. This is where the car indicates a fault and the drive mode selection and all other faults originate. I then disable the interruptor switch and the value returns to 0 and drive modes are reenabled.

View attachment 82052
Does that mean you've got it working the way you want? If so, what did you do? I don't know what the "interruptor switch" is, for instance. The Forscan trace is interesting, but it's the ECU's thoroughly-digested-by-the-computer version of what's happening on the wires, so it's hard to know what's happening voltage-wise in the wiring harness through all this.
 
Does that mean you've got it working the way you want? If so, what did you do? I don't know what the "interruptor switch" is, for instance. The Forscan trace is interesting, but it's the ECU's thoroughly-digested-by-the-computer version of what's happening on the wires, so it's hard to know what's happening voltage-wise in the wiring harness through all this.
No definitely not working right just yet. Going to have to find a way to get a resistor in line to provide the proper feedback to keep things happy after I flip the switch.
 
OK, so potentially shifting stratgies here. Based on the initial post:

Quick explanation of the Grimm Exhaust Valve Defeat Module. The module was designed for people who install exhaust systems without exhaust valves. When you unplug the exhaust valve at connector C4466 and C4467, it creates an open circuit that the PCM sees on pin 11 which is the line that the PCM uses to control the exhaust valves. The PCM detects a fault and throws a DTC code. So the Grimm solution tricks the PCM into believing that there are exhaust valve solenoids out there by using a resistor with the same resistance as the original exhaust valve solenoid coils. Obviously you need 2 because they are plugged into the wiring harnesses where the 2 exhaust valves used to be.

I believe it was VoodoBoss who sourced the harness extensions which are shown between C345 and C4467 on the driver side and C346 and C4466 on the passenger side. The Ford service part numbers for these extensions are:
FR3Z-14A411-H for the drivers side
FR3Z-14A411-J for the passenger side

I ordered up an assortment of resistors and the new strategy will be to develop a "switchable" Grimmspeed exhaust valve simulator. In position 1 the switch will retain factory configuration, In position 2 I want to have the resistors hardwired into an alternate wiring path to accurately simulate the valves. This should allow me to keep the aftermarket switch in position 1 and select the position of the valve I want, then switch the aftermarket switch into position 2 and "lock-in" that valve setting without having to get in and out of the vehicle and reach under the car. With the Verus rear diffuser its extremely difficult (if not completely impossible) to actually reach the exhaust valves.

Based on this post on an Audi forum the valves can be simulated using a 1k ohm 1/2 watt resistor.


Hoping this will work for me as well since the Grimmspeed valve simulator claims to work for a couple of different Audi vehicles as well.

Of course if someone has a set of valves out of the car or a Grimmspeed valve simulator and can measure the resistance it would confirm this theory.
 
Unfortunately it looks like a lot of this has run into a bit of a hurdle as my car's wiring doesn't seem to match up with what I'm seeing on Ford's diagrams based upon the information provided by Ford's website based upon my VIN.

According to this first attachment the sensor wire that controls the valves comes from the BCM on a violet wire and passes through connector C264 on pin #4 in the driver's side footwell. The issue is that on my car there is no violent wire connected to pin #4 at connector C264.

Exhaust Valves.JPG
C264 location.JPG
C264.JPG

On my car there is a blue with teal wire on pin 4 instead of violet and I can't find a single violet wire anywhere in the system. Going to have to chase this through the rest of the harness to see if my car got a blue with teal wire instead of violet for some reason.

52623610485_6621bd4637_o.jpg
52622661757_ddf027f120_o.jpg
 
1,246
1,243
In the V6L
Unfortunately it looks like a lot of this has run into a bit of a hurdle as my car's wiring doesn't seem to match up with what I'm seeing on Ford's diagrams based upon the information provided by Ford's website based upon my VIN.

According to this first attachment the sensor wire that controls the valves comes from the BCM on a violet wire and passes through connector C264 on pin #4 in the driver's side footwell. The issue is that on my car there is no violent wire connected to pin #4 at connector C264.

View attachment 82669
View attachment 82670
View attachment 82671

On my car there is a blue with teal wire on pin 4 instead of violet and I can't find a single violet wire anywhere in the system. Going to have to chase this through the rest of the harness to see if my car got a blue with teal wire instead of violet for some reason.

View attachment 82667
View attachment 82668
Yes, definitely vexing. My 2016 manual shows violet wire as well, although the harness it's in runs down the right hand side of the car through a different set of connectors than yours shows. I expect that the only way to be sure is either with a voltmeter or by looking at the wire color along the path to the tail end at C345. Or, perhaps, check the 2019 or 2020 wiring on the service website - it could be your 2018 got a later harness. There is an as-built manifest for your VIN in the system as well - it'll show what harness you have, etc. I know about it because my friendly parts guy used it to figure out which front wheel studs my 2016 came with. Very handy.
 
If anything mine probably got a late 2017 harness as it was manufactured in November of 2017 (chassis number J0006)

I've been able to locate a violet wire at connector C212 on Pin 34, but on the control side, that's about the only one that makes any sense.

I took at look at Connector C213 and that one does have a pin on the male side (although it's just straight blue) and there isn't a wire at all on the female side of that connector.

Going to take a look at C212 tonight to see what I can figure out there.
 
Well nevermind. C212 pin 34 is a Violet with brown on the female side coming from the firewall, but there isn't even a corresponding wire on the male side of the connector.

I guess I could spend another 22 bucks on access to the Ford parts network again , but not sure I'd get any better information. It may be worth a shot though as I did notice that the wiring diagram is different slightly from the original post for a 2016 and my 2018. Maybe my car got a 2017 harness and it's just drastically different than the 2018 and 2016 harness, but I have my doubts as the only change seems to be at the actual fuse block.

2016
1673566804897.png

2018
1673566833787.png
 
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