Control units not responding... Polo 9N AXR 2002

Hi there,

After a long time of my EPS (Electronic Power Steering) acting up, I wanted to try reading it out with VAG again. At first, I thought it might be due to the new PC (running Windows Vista), so I disabled the firewall and blocked all COM ports except one... but still nothing.


'So, today I used my multimeter to check the vehicle (I checked all the fuses around the fuse box and on the battery, and everything was okay).'

On a Polo from the year 2002, pins 4, 6, 7, 14, and 16 of the OBD connector are used.

Here are the measurements I took... (against a known mass, with/without ignition).

Pin 16: 12-14V (when the machine is running).
Pin 7: 8.7-14V (when the machine is running).

nothing else... the brown one is probably mass, but where do the other (missing) signals usually come from?

'There's a non-factory radio installed, but it's completely disconnected, and all the wiring harness has been removed (from the radio).'

Does anyone have any advice?

Thank you.

Quote:

Does anyone have any advice?

How is anyone supposed to get advice if you don't even specify which diagnostic software and hardware are being used?

First, I would check if the problem is with the car itself or the diagnostic equipment -> take it to a dealership and have them read the error codes.

The friendly people aren't coming inside because they haven't even thought of the possibility that the vehicle isn't responding, and no one has come up with the idea to try using the radio.


My interface is a USB device from xxltech.com and the software is VAG 311.

Sure, then ask the guys at xxltech.com.

They are not responding to my emails. The last time I checked the device, at the end of last year, a different radio was installed, but that can't be the cause because the radio is now completely removed.

'It's probably just a matter of missing voltage.'

Are there any other fuses besides the one on the battery and the one in the fuse box located on the side panel of the instrument panel?

They are not responding to my email. The last time I checked, at the end of last year, a different radio was installed, but that can't be the cause because the radio is now completely removed...
...


I can definitely imagine that being the case with sentences like those.

Since all the punctuation marks are missing, I can only guess what your questions are.


Okay, let's start from the beginning again.

'A radio OE (Original Equipment) was used for an extended period without an adapter. This has now been completely removed. If this is the case, you can discard various control units. The associated diagnostic device may also be damaged if it is not protected against this. These devices are usually not cheap.'

It's only a matter of time before the voltage is present.

Nö .... I see it differently.
Pin 4+5 on the OBD connector is ground, and pin 16 is 12V. Both of these are present in your vehicle.
Pin 15 is the K-bus... It seems to be present, otherwise there would be no voltage there.
I can't say off the top of my head whether your car has a K2 or L bus, but if it does, there would also be voltage on pin 15.
You might not be able to measure the CAN Low and CAN High signals on pin 14 and pin 6 with a multimeter without 'stimulating' the CAN bus.

'The strange thing is that with a friend's OBD handheld device, it's possible to read the car's engine, EPS (Electric Power Steering), and ABS (Anti-lock Braking System) without any problems, even including the radio.'

I'm going to borrow some organic Rosstech from a friend and then I'll post again.

The strange thing is that with a friend's OBD handheld device, it's possible to read the car's engine, EPS (Electric Power Steering), and ABS without any problems.
....


So, it looks like your interface is probably defective.

That's an issue for the interface manufacturer and doesn't belong here.

/viewtopic.php?t=7589 - Point 5