New user

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New user

Postby Martinjensen » Mon Jan 09, 2017 10:55 am

Hi,

I have recently purchased a 4 axis NVH Diagnostics Kit.
I am trying the kit on my own car (Audi A4 1,6L Manual 2005), before attempting to diagnose a customers car.
My car has a speed related vibration, that i would like to identify using my new NVH Tool.

I have a couple of questions:

1: I am trying to input gear ratios, but i cannot get them to display in the graf.
2: I can see that i have a T1 and a T2 vibration. How do i add T5 and T6?
Im asking because that in the help files is written that a failing Outer CV joint causes a T6 vibration
3: I have a vibration at approx 2Hz that is coming and going, what could cause that, is it just road noise?
4: The program has difficulties establishing connection with the car. When it is trying to communicate, the warning light for the vehicle stability system comes on, and the instrument cluster restarts. It is only possible to establish communikation if i turn ignintion on and off several times. When it estabilishes communication i kan drive for hours without a problem. Im am using the Mongoose ISO2 cable supplied with the NVH set.

Im am verry exitet about my newest Pico add on.
I have a 4 channel Pico and the WPS and i love it. :-)

Sorry for my English.

Regards Martin.
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Re: New user

Postby Martinjensen » Mon Jan 09, 2017 11:10 am

Screenshot:
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Re: New user

Postby Steve Smith » Mon Jan 09, 2017 9:50 pm

Hello Martin and thank you for the post, welcome to the forum.

Please don't apologise for your English as I fully understand your post and text

1. I have downloaded and viewed your file and can see you have entered 5 Manual gears but no gear ratios.

Could you confirm ratios were entered and Apply Changes selected before your road test?

2. Displaying T5 and T6 will require the use of harmonic rulers or adding a Custom Vibration.

Clicking on Add Vibration at the Record and Analyse screen will allow for tyre order vibration to be indicated up to T4.

In order to locate T5 and T6 increase the Harmonic Marker Count to 10. See forum post below
https://www.picoauto.com/support/post49451.html#p49451

Click anywhere on the Record and Analyse Frequency view and drag your mouse to the right where 10 harmonic rulers will appear.

Align your first harmonic ruler with T1 (Fundamental vibration) where all subsequent harmonic rulers will display multiples of T1 so revealing T5 and T6 (See Image below)

HARMONIC RULERS.jpg
Harmonic Ruler settings


3. The 1.5 to 4 Hz vibration is very sporadic in nature (in the vertical ((Y)) axis) and is most probably the road surface creating a disturbance in the chassis detected by the accelerometer.

The energy level is low and momentary hence the sporadic nature when viewed in the Frequency display
Given these peaks are neither stable and prolonged (over 2.5 seconds) they can be ignored.

4. Difficulty establishing communication with the vehicle via Mongoose is very odd as this lead is both stable and high speed.

Could you confirm you experience the same symptoms with the Stability Warning Light and instrument panel when communicating with another scan tool? (i.e to read fault codes)

Could you test the NVH and Mongoose hardware/software with another vehicle too?

It is not unusual for the Stability Warning Light to illuminate when connecting a scan tool to the vehicle as a fail safe feature during road-tests.
Often ABS/Stability control is disabled when communication is "ongoing" between scan tool and vehicle network.
The technician is informed of such status by the illumination of either the Stability or ABS warning light (Or both)

What is odd is the instrument panel re-start? Maybe others have seen such events and could add to this post?

To assist you here further, could you activate a feature called OBD logging?
This will enable additional logging information to be obtained during communication between the Mongoose and the vehicle. (See image below)

ENABLE OBD LOGGING.jpg
OBD Logging


This data is then saved in the trace file which can be forwarded to support@picotech.com for evaluation. (Ref this forum post)

To locate the trace file could you download the self help file below and refer to page 4 ?
This has the full description on how to identify the relevant trace file which is created upon closure of your NVH software

TRACE FILE LOCATION PS AND PD.pdf
Trace file location-see page 4
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Creating a Custom Vibration.

To create a Custom Vibration (T5 and T6 in this case)

Click on Add Vibration followed by Add (This will open the vibration configuration box)

Using T1 as the Source frequency enter "6" as your Correction Factor. This will now create a Custom Vibration with a multiplication factor 6 times that of T1 (in other words T6)

Enter a Display Name and Short Name. This allows you to specify how your Custom vibration will be displayed in the various views (Frequecny, 3D Frequecny, Bar Grapgh etc)

Once complete click on OK and then Add Vibration to Select, View, Delete or Edit your Custom Vibration.

The image below should help with the creation process

Custom Vibration.jpg
Adding a Custom Vibration


I hope this helps, take care.......Steve
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Re: New user

Postby Martinjensen » Wed Jan 11, 2017 10:48 am

Hello Steve.

Thank you for the detailed and verry useful reply.

1. Regarding the gear ratios, it was my mistake, i typed the final gear ratio in the wrong box.
Could you explanin the difference in the 4 bokses highlighted, in the attached image?
It would be usfull if the final ratio would allow for 3 decimals in the ratio, like in the other gears.

2. The T5 and T6 can now be wiewed, thanks to the harmonic marker Count or the custom vibration option, this Works perfect :-)
I have changed the language to English, the Harmonic marker Count, was translated in a way that it dident made any sense to me :-)

3. Could be road noise from tires, (Brand new Yokohama Winter tires)

4. Regarding comunication issues, the illumination of the stabillity light is not a safety feature. but is because of communication fault on the CAN Network. When i try to establish connection, engine, ABS, and Airbag management flags error codes for communication on the CAN powertrain Network.
Note this dosent happen with any other tester communicating with the car.
The "restart" of the instrument, is because of the missing data on the CAN Network.

When i try the NVH software on my wifes car (KIA Picanto 1,2petrol 2012) there is no issues at all.

I vil forward the tracefiles to the mailadress provided

Again a big thanks for taking the time to answer my questions.

I now have a better understanding of the program, and can begin diagnosing the vibration, the 4. channel should be usefull for this.
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Re: New user

Postby Steve Smith » Fri Jan 13, 2017 2:26 pm

Hi Martin, thank you for the valuable feedback.

I have created a bug report for the engineers re the symptoms you describe with the Mongoose J2534 connection.

I will add a New Feature Request for the differential ratio entries to accept 3 decimal places.
For now we will have to round up the 3rd decimal place.

With regards to the four boxes, could you indicate if there are translation concerns here as I can forward this information onto the Publications Team?

The image below will assist with the English translation, I hope this helps.

NVH FINAL DRIVE DESCRIPTION.jpg
English description


The front differential ratio entry option has been divided for those transmissions housing 2 x final drive options.
Gears 1 through to 4 use one output-shaft/pinion to create one final drive ratio, whist gears 5 and 6 may utilise a different output-shaft/pinion with a different tooth count acting upon the same crown wheel to generate another final drive ratio.

A New Feature Request has been added to allow for customisation of the gear ratios using alternative output-shaft options (For example Front Differential Ratio 1. Using gears 1, 3 5 and 7)

I have to say, this time of year certainly generates complaints of cabin noise with regards to winter tyres and their “chunky treads” (Tyre pattern noise)

Such tyre patterns trap and compress greater volumes of air between the tread pattern and road surface. This compressed air is then released as the tyre rotates, creating a popping sound.
Now increase the frequency of this popping sound and you have a tyre roar.

There is a link in the following forum post which covers NVH theory and which will help with such diagnosis
topic13781.html

Depending on brand, you cannot fail to notice the increase in tyre noise after driving for 6 or so months on Non-winter tyres.

Take care…….Steve
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Re: New user

Postby Martinjensen » Tue Jan 31, 2017 10:33 am

Hi Steve.
There are no problems with the translation. :-)
I've looked in the help files but could not find a description of the function of the 4 boxes.
But thanks too your answer it is now perfectley clear. :-)
The thing that had me confused, was the 2 different final drive options. One from 1-4 and one for 5-6. The transmissions, with 2 final drive options, i am used to, do not have that layout. But you already covered that in the feature request.

Tanks Martin.
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