fault p1031

PlasticMac

Member
I think it is a solenoid valve, I've seen it referred to as such. Not sure if it's proportional or open/closed though.
Mac.
 

PlasticMac

Member
I am wondering if the VCDS key (the file Rosstech send you, a. vca file) ), has been installed fully? Worth checking perhaps. Sounds like the Basic Settings functionality is not enabled (as with the free version), which the . vca file does.
Mac.
 

lfield

Member
I am wondering if the VCDS key (the file Rosstech send you, a. vca file) ), has been installed fully? Worth checking perhaps. Sounds like the Basic Settings functionality is not enabled (as with the free version), which the . vca file does.
No, this is fine. I see on the about page it is registered and it picked up my details correctly from the .vca file. I could also run the auto scan which is not enabled when not registered.
 

lfield

Member
I plan to investigate in more detail tomorrow and will probe the connectors. Does anyone know what I should expect to find on connectors to the control value (N316) and potentiometer (G336)?
 

PlasticMac

Member
I'd start by unplugging the N316, and measuring the resistance (ohms) of the valve coil,to check for open or short circuit, which would point to a faulty valve. If you see a resistance, I'd guess 50 - 100 ohms, the valve is OK electrically. I'd also guess, that at rest, there would be little or no voltage to the valve, with voltage only being applied as revs rise above 2500 - 3000. Lots of guesses in there though.
Mac.
 

lfield

Member
I unplugged N316, as a side note VCDS did not detect that this had been unplugged (no open circuit error). The resistance was 32.6 Ω, Green/Yellow wire 11.9v, Purple/Yellow 3.6v. To me there is nothing obviously wrong with that sensor or connection. I confirmed that the linkage moved when I sucked on the vacuum pipe and that the connector was plugged correctly. Running the adaption, the measuring block 142 showed the same as I wrote in the previous post and clicking on basic settings showed the same, nothing changed after leaving it for a couple of minutes. Is there a way for VCDS to show the output of the potentiometer (G336). It is difficult to access. Do I have to strip down the intake manifold again to access/replace?
 

PlasticMac

Member
I unplugged N316, as a side note VCDS did not detect that this had been unplugged (no open circuit error). The resistance was 32.6 Ω, Green/Yellow wire 11.9v, Purple/Yellow 3.6v. To me there is nothing obviously wrong with that sensor or connection. I confirmed that the linkage moved when I sucked on the vacuum pipe and that the connector was plugged correctly. Running the adaption, the measuring block 142 showed the same as I wrote in the previous post and clicking on basic settings showed the same, nothing changed after leaving it for a couple of minutes. Is there a way for VCDS to show the output of the potentiometer (G336). It is difficult to access. Do I have to strip down the intake manifold again to access/replace?
Hi,
When you took the voltage readings (Green/Yellow wire 11.9v, Purple/Yellow 3.6v), were these between those wires, and grnd/chassis? If so, I'd expect one to be 0v, assuming it's a two wire solenoid.
Mac.
 

Andrew

A2OC Donor
Hi,
When you took the voltage readings (Green/Yellow wire 11.9v, Purple/Yellow 3.6v), were these between those wires, and grnd/chassis? If so, I'd expect one to be 0v, assuming it's a two wire solenoid.
Mac.
Definitely two wire. - Andy

image.jpeg
 

lfield

Member
When you took the voltage readings (Green/Yellow wire 11.9v, Purple/Yellow 3.6v), were these between those wires, and grnd/chassis? If so, I'd expect one to be 0v, assuming it's a two wire solenoid.
The measurements were made between the pin and the alternator case.
 

PlasticMac

Member
The measurements were made between the pin and the alternator case.
I'm wondering if there's a wiring problem between the N316 and the controller. Those voltages don't seem right, like they are "floating" and no errors with it disconnected, it should report "OPEN" surely?


very strange.
Mac.
 
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Andrew

A2OC Donor
We need the measuring block numbers for the G336. We also need a VCDS Guru, so we can log that data while driving, and monitor the flaps in real time. Will continue to look for the answers.
Mac.
Is the old post #25 above before this current thread revival any use? - Andy
 

PlasticMac

Member
Yes, I think it is. Wondering what the voltage coulmn is. Potentiometer output, or applied volts to the N316?

Thinking more about no error when N316 is unplugged, as it's a controller output (rather than an input from a sensor), maybe it's not monitored, with diags relying on the potentiometer. That constant voltage could mean no variation from the pot (no movement, or duff pot) or voltage applied to the N316, which doesn't vary because the controller sees no movement. Taking the same log, while manually moving the potentiometer might clarify. This could be done via sucking the vac line, as (recent) OP did to check flaps.
Sorry it's all a bit vague, just trying to visualise what should be, and what is going on.

EDIT: "Taking the same log, while manually moving the potentiometer might clarify"
This could be done via sucking the vac line, as (recent) OP did to check flaps.
Mac.
Here's the log from #25:
Capture vcds1.PNG
 
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