• Registered: 2021-10-24
  • Posts: 3

Topic: No communication trough OBD

Hello Stefan.

I am a happy FIS-CONTROL user, but i detected a problem that i did not have before installing your great product.

Let me explain, my car is an Audi S3 8L 2002 with RNSE and bluetooth OEM working correct.

The car its remapping with REVO from many years a go, and they have a utility called SPS, this item communicates with the ecu through the OBD port, to change boost, timing or gasoline settings.

Well, in order for it to communicate with ecu there are some cars of group VW, that it is necessary to remove the fuse from the instrument panel.
Before install FIS-CONTROL, is what i usually did and without major inconvenience.

My problem is that as a result of having the FiS-CONTROL installed, I can no longer communicate with the car's ecu using the REVO utility.

I remove the fuse from the panel, put the ignition on, and I have no communication with the ecu or any controller of vehicle, not even using a simple VAG-COM cable, when before i could connect without problems.

Could you help me?  There would be some way to deactivate FIS-CONTROL briefly without having to physically de-install it.

Or some method of configuration so that when I remove the fuse from the instrument panel, I can continue to have communication with the rest of the car's components, especially the ecu, through the OBD socket. (except the instrument panel logically) smile

Many thanks for your time, and excellent product!

  • From: Hessen / Germany
  • Registered: 2015-01-01
  • Posts: 2,135

Re: No communication trough OBD

Ok, I think the problem is that the FIS-Control is powered from the same fuse as the instrument cluster.
If the FIS-Control is unpowered, it may block the communication on the OBD line.

Do you really need to pull the fuse?

stefan@fis-control's Website

  • Registered: 2021-10-24
  • Posts: 3

Re: No communication trough OBD

Yes, I afraid it is necessary. (I attaching a link so you can see that i not crazy, hahaha)

https://ibb.co/jVxMJ3s


Any suggestion?

  • From: Hessen / Germany
  • Registered: 2015-01-01
  • Posts: 2,135

Re: No communication trough OBD

Hm, sorry, In this special case I have no idea how to solve it without unplugging the FIS-Control.
If you flash your ECU often, you may consider installing a switch in the K wire that goes to the FIS-Control.
This is pin B1 at the FIS-Control (see here: https://fis-control.de/files/kabel.pdf)
So instead of unplugging the FIS-Control you just disconnect its K wire with the press of a button.

stefan@fis-control's Website

  • Registered: 2021-10-24
  • Posts: 3

Re: No communication trough OBD

Ok, I had thought that there would be some way to trick it via software.

I will put it an on/off button.

An instructive question. Why is OBD port communication blocked, when FIS-CONTROL has no power?

  • From: Hessen / Germany
  • Registered: 2015-01-01
  • Posts: 2,135

Re: No communication trough OBD

Software only helps when the FIS-Control is powered.

I have not verified that, but I assume that the FIS-Control pulls the OBD line towards GND when it is not powered. Whereas it should be pulled to 12 volts for normal operation.

stefan@fis-control's Website