Evo VI Evo Link DBW Error

[robrixon]

Hi All,

I am helping a mate try and get to the bottom of a TPS error 75. It's a G4+ Evo Link with a Evo X pedal and DBW TB. I haven't seen the car in person yet but he's sent enough images to figure out the wiring.

Whoever installed the DBW has used a DT04-08PA receptacle to split out 5V and sensor grounds on the XS loom to supply the pedal and Evo X throttle body. They've also crimped an extra power and ground heading back out of the DT06-08SA which all makes sense.

The odd part is an extra wire (green) which is crimped with the yellow Volt 7 signal back to the ECU. This wire is TPS Main on the Evo X throttle body. Could this have been done to keep the AYC happy? This isn't in the wiring diagram because I don't yet know where it's going.

The tuner reckons the internal relay for the DBW may be "glitching" (is this a known issue?), but I'm wondering if the TPS main signal is noisy? Surely it would be better to output the TPS from the ECU as a separate signal to the AYC rather than splicing into it?

Thank-you in advance. If the advice is "look at the damn car in person first" that's probably fair enough...

[Adamw]

What makes you think there is a wiring issue?  Under what conditions does the error occur? or does it not work at all?  Can you attach a copy of the tune and a log of the error occurring.  Do the TP and AP calibrations succeed? 

 

3 hours ago, robrixon said:

The odd part is an extra wire (green) which is crimped with the yellow Volt 7 signal back to the ECU. This wire is TPS Main on the Evo X throttle body. Could this have been done to keep the AYC happy?

but I'm wondering if the TPS main signal is noisy? Surely it would be better to output the TPS from the ECU as a separate signal to the AYC rather than splicing into it?

Yes the green wire is likely AYC, and yes it is normal to share it with both ecu's. 

 

3 hours ago, robrixon said:

The tuner reckons the internal relay for the DBW may be "glitching" (is this a known issue?)

There is no DBW relay on this ecu. 

 

 

[robrixon]

Thank-you for the quick reply. Tune attached. Apologies for the second hand info, I am passing on the owner's description. I will try and get a log as soon as possible.

1 hour ago, Adamw said:

What makes you think there is a wiring issue?  Under what conditions does the error occur? or does it not work at all?  Can you attach a copy of the tune and a log of the error occurring.  Do the TP and AP calibrations succeed? 

Callibrations are successful. It's an intermittent issue that apparently is hard to pin down to a particular condition. Most recently during a track day on the weekend the car would keep going into limp mode after the error occured. Also occurs street driving, on-off throttle, steady part throttle... Clearing the error and doing a calibration gave it another lap or so on the track.

1 hour ago, Adamw said:

Yes the green wire is likely AYC, and yes it is normal to share it with both ecu's. 

Excellent thank-you.

Regarding the relay I must have misunderstood your post on this thread: https://forums.linkecu.com/topic/16193-evo-dbw My understanding from that thead was that the ECU was powering the Aux on the expansion connector #2 to power the DBW motor and a dedicated relay wasn't required. On this setup the tuner has used Aux IGN 8 (instead of Aux 16).

On 6/18/2022 at 7:12 AM, Adamw said:

E-throttle power is done internally on the evo plug-in so you dont need to wire a physical relay, you just need to assign an unused aux to E-throttle relay 1.  I would suggest Aux 16 since you cant use it for anything else.  

Assign aux 4 to "E-throttle signal 1" and Aux 9 to "E-throttle signal 2".

Evo-map.pclr

[Adamw]

TP/Target error is usually a tune issue, the throttle is either taking too long to reach target, or the PID is too aggressive so an unstable oscillation sometimes initiates.  Set up ECU logging to record all the common E-throttle related channels, including the error accumulators etc so you have some data next time it occurs.  

[robrixon]

I've got some data on this now. The vehicle owner logged a whole session so the file is too big to upload but I've exported two examples of the issue as CSV. Not all parameters that might be useful were logged (error accumulators) but hopefully it's some help. It looks like the target can't be achieved momentarily and the throttle loses the plot in trying to make it happen.

Throttle Error Example B.csv Throttle Error Example A.csv

[Adamw]

Yes, this is the oscillation that I mentioned above.  The PID needs tuning.  I would start by dropping the max min DC down to 90% as shown in the EvoX throttle settings in the help file and you will possibly have to reduce proportional a little too.  

[robrixon]

Thank-you Adam will try those changes and look at the proportional.