Please I need help with wideband a/f ratio autometer(99 cobra)

[Arthur]

Hi everyone! I recently purchased an autometer air/fuel ratio wideband gauge from summit racing and I have problems with it.
All hooked up the way instruction says red-to power turns on when you turn on the ignition 12v, brown to constant power 12v, black-ground, white to a light dash dimmer(works), blue for ecu data(not used).

The problem is when I turning the ignition or powering directly from the battery(also did as an option) it counts from 20 to 0 and stops at 17.0(see the picture) with the sensor plugged in and 15.0 if sensor disconnected and it does not matter if car runs or if you just turned ignition key to on position. I already contacted summit racing and all they did is sent me another one and this new one does exact the same. Does it not compatible with my car or it just bad brand. I also google it and found another website someone had the same problem but it looks like they did not solve it.
Please, I am very in need of help with it!!!

 

[01yellercobra]

Are you running the brown wire connected or with a switch in place? Where did you ground the unit?

 

[Arthur]

Are you running the brown wire connected or with a switch in place? Where did you ground the unit?

I ran with and without brown wire(no switch) and it does the same. Also summit racing sent me a replacement and I installed all from the beginning and it still shows the same 17...
The ground goes from the body but I also tried directly from the battery and no change.

 

[Arthur]

Ok just did this test: and it works exactly like on the video but from 10-17 only since the gauge allows.
Is that mean my car runs lean?

 

[01yellercobra]

Can you post a video of the turn on sequence and then a few seconds of the engine running? Even if the car is lean it'll bounce around. Where did you mount the wideband?

Hopefully applying power to the red and brown wire at the same time didn't fry anything.