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Problem: P08AA – Clutch Pedal Position Sensor Circuit High

Symptoms: Cannot use features like flat-foot shifting or launch control. Car can be started without clutch in. Clutch position sensor on my AP reads 67% clutch engagement with my foot off the clutch instead of 0%. Clutch position sensor reads 100% when pressed all the way in.

Happened after replacing the master cylinder over a year ago. I couldn’t get the clutch sensor to clip in, so I left it out for about 6 months before eventually getting under and putting it back in.

Tried: Cleared codes. Cleared KAM. Reset PCM the oldschool way. Reset PCM through ForScan. Replaced both clutch sensors on the pedal, (sensors that sense when the clutch is in or out, as well as the sensor on the master cylinder, as well as the entire master cylinder assembly itself, because at this point why not? Inspected the wiring for damage and found none.

I’m at a loss – is there something I am missing, like a clutch reset or re-learning procedure?
 

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Problem: P08AA – Clutch Pedal Position Sensor Circuit High

Symptoms: Cannot use features like flat-foot shifting or launch control. Car can be started without clutch in. Clutch position sensor on my AP reads 67% clutch engagement with my foot off the clutch instead of 0%. Clutch position sensor reads 100% when pressed all the way in.

Happened after replacing the master cylinder over a year ago. I couldn’t get the clutch sensor to clip in, so I left it out for about 6 months before eventually getting under and putting it back in.

Tried: Cleared codes. Cleared KAM. Reset PCM the oldschool way. Reset PCM through ForScan. Replaced both clutch sensors on the pedal, (sensors that sense when the clutch is in or out, as well as the sensor on the master cylinder, as well as the entire master cylinder assembly itself, because at this point why not? Inspected the wiring for damage and found none.

I’m at a loss – is there something I am missing, like a clutch reset or re-learning procedure?
Disconnect the battery and let it sit for 15 min then reconnect it.
 

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Any solution for this?
Do you have an Accessport? If so, you would switch one of your gauges to "clutch pedal position" and make sure it reads 0 at rest, 100 at full press, and smoothly activate the clutch while watching the gauge, and look for flat spots in the percentage reading.

Well. You'd have to verify that both clutch pedal sensors are fully plugged in. I've had one be half plugged before. In this case it was the sensor closest to the driver.

Once that is verified, then inspect both of the "plungers" on the switches for damage or deformity. Also check the two areas those plungers ride on, for obstructions.

Now you should grab each sensor individually, and gently try to wiggle them around, if they are falling off the pedal assembly, or super loose, this can cause issues.

While you are in there, check the wiring to each switch for damage.

If there isn't a smoking gun at this point. You can just replace the sensors anyway, to rule out the variables.
 

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@Duece McCracken Thanks for taking time out to reply, I had OBD2 reader with me so I checked and yes you are right it thinks its 66% pressed in even when foot is off. So I ordered both switches for CPP sensors. I'll update once I replace them.
 

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@Duece McCracken Thanks for taking time out to reply, I had OBD2 reader with me so I checked and yes you are right it thinks its 66% pressed in even when foot is off. So I ordered both switches for CPP sensors. I'll update once I replace them.
Pay close attention to how they are installed, and which sensor goes in which location. iirc the rear one can be a PITA to re-install.

I can help you out if you run into trouble. I have replaced that whole clutch pedal assembly a few times.
 

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Pay close attention to how they are installed, and which sensor goes in which location. iirc the rear one can be a PITA to re-install.

I can help you out if you run into trouble. I have replaced that whole clutch pedal assembly a few times.
I actually replaced the whole master cylinder along with the clutch pedal, I think it wasn't installed properly.
Also a new clutch, I hope nothing is wrong with the PCM and I get my CC back.
 

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So...I have this code after an engine and tranny remove and replace. I removed the clutch pedal assy during the process. So...I've replaced all 3 clutch sensors, the 2 inside the car AND the one on the clutch master cylinder snapped to the side of the clutch assy inside the engine comp behind the battery box....no dice. So..in addition...I cant start tuning the car because when I hit 5k RPM the rev limiter kicks presumably because I'm on a tune with flat foot shifting enabled and it thinks the clutch is depressed. I have the exact same reading as the OP, 67 when the clutch is out and 100 when its depressed.

Anyone ever solve this?

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Update: Took the car to Ford (same dealership I ordered the new pedal and master cylinder sensor from) they trouble shot it and determined the brand new sensor I just installed was bad. Because I installed it, and not a Ford dealership I had to pay the labor charge. They replaced the whole clutch pedal with the new sensor and fixed the error code. $360 in labor because Ford sold me a defective brand new part, sigh. Sadly they F-ed something up because air is getting into the clutch line causing a spongy pedal and sticks to the floor. Waiting for them to fix whatever they F'd up. Anyways...that was my P08AA saga.

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Update: Took the car to Ford (same dealership I ordered the new pedal and master cylinder sensor from) they trouble shot it and determined the brand new sensor I just installed was bad. Because I installed it, and not a Ford dealership I had to pay the labor charge. They replaced the whole clutch pedal with the new sensor and fixed the error code. $360 in labor because Ford sold me a defective brand new part, sigh. Sadly they F-ed something up because air is getting into the clutch line causing a spongy pedal and sticks to the floor. Waiting for them to fix whatever they F'd up. Anyways...that was my P08AA saga.

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Which sensor did you end up changing since I also got both sensors replaced. Could I be a victim of bad new sensor?
 

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Which sensor did you end up changing since I also got both sensors replaced. Could I be a victim of bad new sensor?
It was the one on the pedal. They replaced the whole clutch pedal assembly with the sensor on it, and fixed the problem. Ford tech said the sensor on the pedal, that I had JUST replaced 2 days prior was bad.



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It was the one on the pedal. They replaced the whole clutch pedal assembly with the sensor on it, and fixed the problem. Ford tech said the sensor on the pedal, that I had JUST replaced 2 days prior was bad.



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Technically when changing my clutch I also put in a band new master cylinder which didn't come with sensors. I guess I will take it in and let them look at it since I miss my cruise control now.
 
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