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Discussion Starter #1
Hey! My cars CEL randomly came on yesterday and it gave me the code: P0806 Clutch Position Sensor Circuit Range/Performance Malfunction. I've been reading up on this and it seems that only manual cars can get this code, but if an automatic gets it that may mean that there is something wrong with the ECU/PCM. I was thinking of taking a look at the ECU/PCM box, unplugging all the cables and giving it a good cleaning to see if that was the issue. What do you guys think?
 

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One source seems to agree with you (red is mine and seems to relate to auto box):

What repairs can fix the P0806 code?
The most common repair for the P0806 code is replacing the clutch position sensor or readjusting the sensor. However, other repairs can include repairing damaged wiring, cleaning corroded connectors and (rarely) replacing the PCM.

https://www.yourmechanic.com/article/p0806-obd-ii-trouble-code-clutch-position-sensor-circuit-range-performance-malfunction-by-valerie-johnston
 

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So once I check out the ECU, check out the wiring, and maybe give them a good cleaning, if the CEL is still on would I have to replace the ECU? May I ask, is there a diagram that shows where the Clutch Position Sensor Circuit is so that I know what I'm looking at?
 

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Manuals dont have a clutch sensor... (that I know of) to me it's either the supercharger clutch or something inside the transmission.
 

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diagram might be there or not

are you on a phone or pc? did you see wiring diagrams for your r170?
 

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Discussion Starter #9
Manuals dont have a clutch sensor... (that I know of) to me it's either the supercharger clutch or something inside the transmission.
Welp. Is this a sign that the transmission is starting to wear out? If not, thank god, haha! If so, what is my next step to either fixing this or figuring this problem out? I love this car dearly, but will I may have to purchase a new one? The car itself runs and shifts fine, the CEL just came on with that code for some reason.
 

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Welp. Is this a sign that the transmission is starting to wear out? If not, thank god, haha! If so, what is my next step to either fixing this or figuring this problem out? I love this car dearly, but will I may have to purchase a new one? The car itself runs and shifts fine, the CEL just came on with that code for some reason.
The 722.6 doesn't go bad unless you hear bad noises! If anything, it's a conductor plate or 13 pin connector that gets dirty. maybe someone else can translate the trouble code a little better?
 

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The clutch in question will be the supercharger electromagnetic clutch that is not operating.
Possible causes are...

The electric coil has failed that energises the pulley or the connector is bad/dirty and giving a poor connection. Could also be the K40 relay board as this supplies power to the ecu.
 

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Discussion Starter #14
The 722.6 doesn't go bad unless you hear bad noises! If anything, it's a conductor plate or 13 pin connector that gets dirty. maybe someone else can translate the trouble code a little better?
That's reassuring! I'll grab some electrical cleaner and get to work! That is, if that solves the issue haha
 

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Discussion Starter #15
The clutch in question will be the supercharger electromagnetic clutch that is not operating.
Possible causes are...

The electric coil has failed that energises the pulley or the connector is bad/dirty and giving a poor connection. Could also be the K40 relay board as this supplies power to the ecu.
So, the electric coil is bad, the connector is bad/dirty and needs to be cleaned, or the K40 relay has gone bonkers. Which one of these solutions should I try first?
 

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Personally I would disconnect the supercharger wiring connector and check it. Also check the wires are still good as vibration can cause them to fail at the connector. If all looks good then using a multi-meter measure the resistance of the clutch coil which I seem to recall should read approx 3 ohms. If again all is well then move onto the K40.
 

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Discussion Starter #17
Personally I would disconnect the supercharger wiring connector and check it. Also check the wires are still good as vibration can cause them to fail at the connector. If all looks good then using a multi-meter measure the resistance of the clutch coil which I seem to recall should read approx 3 ohms. If again all is well then move onto the K40.
Is my car safe to drive for now? Or should I put it up until I'm able to fix this P0806 code?
 

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Discussion Starter #19
If it is the electromagnetic clutch coil that is failing then this can cause damage down the line if it shorts out.....
Since the electromagnetic clutch coil is failing, does that mean it's staying closed when it should be open? With that, if I'm able to find a way to keep it open all the time would that be bad for the car? Also, where is the electromagnetic clutch coil?
 

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Discussion Starter #20
Update!

I was driving around today and I decided to re-check the CEL with my OBDII sensor (I know that it is dumb, but I'm secrely hoping that the P0806 code switches to something much easier to fix such as a P0170 code haha). Anyway, I take a look and I now have another code! In addition to the P0806 code that I have I also have a P0410 Secondary Air Injection System. Does this relate to the original P0806 code or is this another stand alone problem?
 
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