Signal noise problem

[Touge Master]

Hi there,

I've encounter a problem with a customer car.

Car was tuned using my PLX M300 TE wideband. I wired it this way:

- Red 12v switched to pin A25
- Black Controller and heater grounds to ECU ground below thermostat housing
- Grey WB signal to pin D14

Datalog showed signal was clear. Can be seen here.

Pre.jpg

Then i removed my wideband and wired customers own wideband (Innovate LC1) this way:

- Red 12v switched to pin A25
- Blue and White Controller and heater grounds to ECU ground below thermostat housing
- Yellow to pin D14
- Voltage offset was low. Less than -0.1

Datalog showed that the wideband was causing some interference as signals were noisy. Can be seen here.

Post.jpg

I've tried this grounding the wideband this ways:

- Blue to thermostat housing. White to Pin A24.
- White to thermostat housing. Blue to Pin A24.
- White to pin D22. Blue to thermostat housing.
- White and blue both to pin D22 using a piece of metal so they don't share same ground point.
- Voltage offset is always very low around -0.06_-0.03

Nothing seems to work to make signal clear.

I'm lost in this. Do you have any ideas for solving this?
Thanks in advance.

[Hondata]

White (system ground) must go to the same ground as the ECU, but you could put the heater ground (blue) straight to the battery negative.

The +12V does not need to come from A25, so you could take this from the fuse box.

Also check the transmission and valve cover ground straps, and clean the contact points.

[Touge Master]

White (system ground) must go to the same ground as the ECU, but you could put the heater ground (blue) straight to the battery negative.

The +12V does not need to come from A25, so you could take this from the fuse box.

Also check the transmission and valve cover ground straps, and clean the contact points.

Thanks for the reply.

Where do you think i should ground the White wire? Thermostat housing ground point (ecu)?, A24?, D22?

Is the wideband putting any noise into the ECU through A25 (+12v)?

Why my PLX worked flawless and the Innovate is causing so much trouble?

[Spunkster]

Do not ground it at the ECU. Ground it at the actual thermostat housing.

Also the D14 input is not the best to use for a wideband input. YOu would be much better off using one of the other inputs. D14 cannot use the full 0-5v range.