B8 S4 bypass value issue/Terminal Voltage issue.

   #81  

Dr Sheldon

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I feel like this issue is beyond the realm of a standard mechanic

Also you do not have the tooling to make the measurements required.
 
   #82  

Uwe

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Do i need ot pay VCDS for some support here?
Without being able to lay hands (and test equipment) on the car, I really don't think that would be much help.

-Uwe-
 
   #83  

PetrolDave

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Do i need ot pay VCDS for some support here?
VCDS can only do what the VW diagnostics allow, beyond that you may be into getting a chip tuner to 'hack' your ECU.
 
   #84  

B8boi

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@Uwe for any other car I 100% agree with your sentiment, but after studying this simos system, I am pretty impressed with how thorough the system is. I mean every I/O is visible and able to be logged through VCDS.

VCDS can look at so many things, look at any and all inputs for the module in question and variable placeholders, voltages, I feel like I just dont know enough about the values to assert a value is out of normal range. That's why I'm asking for support because I figure I just need some help to think a bit more out of the box on how to use VCDS to monitor parameters and find something out of whack.


i mean ya'll have been very helpful (not without pulling teeth lol) and I'm gracious. but I'm digging for more here because I want to fix this car myself. sorry for being stubborn/not confiding in the stealership/mechanic that has a lazy eye.
 
   #85  

B8boi

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Also you do not have the tooling to make the measurements required.
Such as? Please elaborate what measurement? Clamping current meter? If you think an oscilloscope will suffice and that I need it to get support I will. But frankly anything more than a multimeter and VCDS seems far reaching.
 
   #86  

Dr Sheldon

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But frankly anything more than a multimeter and VCDS seems far reaching.

Frankly, You have no clue how wrong you are !!

Those words come from a wise man that could very likely nail the fault in your within 100 minutes.
 
   #87  

Dr Sheldon

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If you think an oscilloscope will suffice and that I need it to get support I will.

But not just any scope. Digital Storage with 4 channels would be ideal.
 
   #88  

B8boi

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But not just any scope. Digital Storage with 4 channels would be ideal.
Fitting that I have one at work I can borrow! Ill need to read up on how to use it, but I have a ton of equipment at my fingertips I just need the direction where to look and how.

What are you looking for or trying to find with the osci-scope?
 
   #89  

B8boi

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Frankly, You have no clue how wrong you are !!

Those words come from a wise man that could very likely nail the fault in your within 100 minutes.
I mean maybe I am wrong, but VCDS captures values within .1 of a second or so, so using the software i can pretty much graph and view signals much like an oscilloscope would.
 
   #90  

EuroX

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A scope will tell you if you have a good signal or not, visually if you know what you looking for in term of signal you will know right away whether signal is good or not. Once you know that you can start checking why no signal or shit signal. Could be high resistance in a wire could be a loose connection. At this point I wouldn't be surprised if it was a loose connection. Was a ping drag test performed?
 
   #92  

Uwe

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I mean maybe I am wrong, but VCDS captures values within .1 of a second or so, so using the software i can pretty much graph and view signals much like an oscilloscope would.
VCDS can capture values as fast as a control module is willing to supply them. That can be anywhere between about 3 and 30 samples per second, depending on the control module in question.

-Uwe-
 
   #93  

Dr Sheldon

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VCDS can capture values as fast as a control module is willing to supply them. That can be anywhere between about 3 and 30 samples per second, depending on the control module in question.

-Uwe-

Yes indeed and 30 samples per second is not to be laughed at ! Will 3 samples always be enough ?

However it is Serial Processed Data taken within the ECU - Where as the scope will capture Raw Data where ever I choose to place my probe, some measurements are best taken at the component and not within the Module.


further more the limitations on what data I capture are my imagination not a limited list.


VCDS & Multimeter make a great combination and will suffice most of the time, if you dont mind having to guess now and then. The addition of a good Oscilloscope and Accessories can only enhance the chances of a First Time Diagnostic Success.

I have often argued, here in this forum, that the Multimeter has no place in the modern workshop other than to measure 60 ohms across a CAN network.

You need a little more than "basic" knowledge to know how to use a meter and how it can give false positives.
 
   #94  

Uwe

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However it is Serial Processed Data taken within the ECU - Where as the scope will capture Raw Data where ever I choose to place my probe, some measurements are best taken at the component and not within the Module.
No argument. If you want to see, for example, individual pulses from a crank position sensor, or a wheel speed sensor, to make sure that there aren't any pulses missing, you absolutely need a 'scope.

-Uwe-
 
   #95  

B8boi

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Ok so had a death in the family in November and holidays are just a hassle, so starting this back up.
I am trying to debug this issue, but I believe there is something to behold in the fact that I can do the adaptation and it is "failing"

I have an oscilloscope at work that I use and can borrow. But because i can only borrow it for a weekend I need to plan what my check will be with it. The problem is I've been trying to discern what to scope when the car isn't running( but can run an adaptation) and I am realizing all the checks and replacements I have done indicate that my issue wont be detected by oscilloscope. the issue is with a component that does not produce oscillatory feedback. The bypass valve has connection has +,ground, signal, motor + and motor - The Pwm output to motor+ maybe could be scoped, but again, what for?

Like lets say for example I scope the output of the bypass valve motor and see it dropping off in voltage halfway through the adaptation, then what? What am I looking for with an oscilloscope for this issue? The wires directly go from ECU to the bypass..........

Furthermore:
Checked voltages with the car running. Car charges at 14.2 volts. Fluke Meter check, at battery, jump start posts, and from junction and ECU ground are in alignment at 14.2. But VCDS shows 13.5 volts. Something is keeping proper voltage from getting to the ECU. But I cannot for the life of me determine.

Can you guys look at this electrical schematic and see any blaring items that could short out and cause me so much issue?

I tried to disconnect any and all sensors and devices i could find sharing the 5v line but i still cannot adapt the bypass properly indicating me finding the link.

Below is a link for the electrical schematic for the ecu componentry. Help me out plz

 
   #96  

Uwe

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Below is a link for the electrical schematic for the ecu componentry. Help me out plz
Using a plate-of-spaghetti diagram from SomeData? Ick!

-Uwe-
 
   #97  

B8boi

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Is there any other way to have a electrical schematic? haha Dont get me wrong Id love a rigatoni diagram, but I dont believe that's on the menu.

Youre expecting for the ERwin schematic instead? I thought that this one was better because its easier to group the consumers related to the issue? Otherwise I just have the bypass valve isolated on the erwin schematic but it offers no insight what to check outside of standard lines related to the module.
 
   #98  

B8boi

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Using a plate-of-spaghetti diagram from SomeData? Ick!

-Uwe-
Purchasing a product from a vendor that says they'll offer support. but only provides 4 pages of ranting and ego boost. (1 page for ECU cloning actually helped)

Thats a real ick
 
   #99  

Uwe

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Checked voltages with the car running. Car charges at 14.2 volts. Fluke Meter check, at battery, jump start posts, and from junction and ECU ground are in alignment at 14.2. But VCDS shows 13.5 volts. Something is keeping proper voltage from getting to the ECU. But I cannot for the life of me determine.

Can you guys look at this electrical schematic and see any blaring items that could short out and cause me so much issue?
0.7V of drop between the battery and the ECU is not something I'd consider concerning. That's due to the resistance of the fuses, wiring, and connectors between the the battery and the ECU.

Purchasing a product from a vendor that says they'll offer support. but only provides 4 pages of ranting and ego boost. (1 page for ECU cloning actually helped)
Apologies, but support does not have a magic wand that fixes cars remotely. [


-Uwe-
 
   #100  

Dr Sheldon

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Purchasing a product from a vendor that says they'll offer support.

Very Short sighted you are!!

Also you do not have the tooling to make the measurements required.

Frankly, You have no clue how wrong you are !!

Those words come from a wise man that could very likely nail the fault in your within 100 minutes.
Yes indeed and 30 samples per second is not to be laughed at ! Will 3 samples always be enough ?

However it is Serial Processed Data taken within the ECU - Where as the scope will capture Raw Data where ever I choose to place my probe, some measurements are best taken at the component and not within the Module.


further more the limitations on what data I capture are my imagination not a limited list.


VCDS & Multimeter make a great combination and will suffice most of the time, if you dont mind having to guess now and then. The addition of a good Oscilloscope and Accessories can only enhance the chances of a First Time Diagnostic Success.

I have often argued, here in this forum, that the Multimeter has no place in the modern workshop other than to measure 60 ohms across a CAN network.

You need a little more than "basic" knowledge to know how to use a meter and how it can give false positives.
 
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