E-Throttle control via Aux 9&10 (ECU Fault Code 84 Aux9/10 driver fault)

[S4-VR6]

I am experiencing an ECU fault code 83 when I turn the V88 ECU on.  The throttle is snaps open and sounds like the motor is driving the throttle plate into the hard stop until the Aux9/10 output trips on over temp or overcurrent at which point the throttle plate snaps back to the closed position. I have all the E-Throttle protection relay wired as per the generic E-Throttle wiring diagram. I can read changing voltages on both the primary and sub potentiometers on the TPS as well as primary and sub voltage changes associated with the FPS (which leads me to believe that the required I/O channels are configured properly and that the ECU should be expecting to control an E-Throttle).

I have performed a variety of wiring configurations, I can measure change in resistance on both the primary and sub channels of the throttle body itself as well as 2 ohms of resistance through the throttle body 12V motor which leads me to believe the throttle body is OK.

I noticed that the primary is essentially inverse in its resistance scale when compared to the sub channel for the throttle body. i.e. primary is 850-1500 Ohms from closed to open while the other channel is 1500-800 from closed to open

I can perform a FPS calibration with good voltage and % open feedback

I cannot perform a TPS calibration, I receive an error 5 code “main TPS movement code”

I disabled both Aux9 and 10, turned the ECU on, the T-Body did not move but I received the same ECU fault code (how can it be getting an over temp, overcurrent error if it the channel is disabled?)

What is the expected motion of the throttle body on ECU start up? Does it go to full open then back to full closed?

What could be driving the throttle open?

Could there be a configuration issue or something that I have not set up correctly?

Any other ideas or things I can try?

 

Thanks very much!

Bob Osusky

[Scott]

Hi Bob, 

I received your email and have replied. I will include the message below in case someone has a similar problem in the future.

Scott

Hi Bob,

Two possibilities comes to mind:

1. The e-throttle target is high (like close to 100%) and so the ECU drives the throttle to this position.

or

2. The e-throttle motor is wired backwards, so the ECU thinks it is closing the throttle, but it is in fact opening it.

Under normal conditions when the ECU starts up the throttle will be driven to the current target position. If you open the runtime value window (F12 key) and go to the E-throttle tab, and look for the parameter 'E-Throttle Target' you will be able to see what the current target position is.

Best regards,
Scott.

[josey]

lost one afternoon for this, and it was my mistake.

 

test TB on battery terminals and check what is (+) what (-)

unpin aux 9 and 10 from vipec plug, and connect them directly to battery terminal (but for very short time for like less than second)

if you wire it correctly your TB blade should open, if it is closing, reverse terminals on battery and try again.

return aux 9 and 10 back to vipec plug but this time with correct polarity.

delete errors

that should do the trick

 

 

 

 

[Scott]

lost one afternoon for this, and it was my mistake.

 

test TB on battery terminals and check what is (+) what (-)

unpin aux 9 and 10 from vipec plug, and connect them directly to battery terminal (but for very short time for like less than second)

if you wire it correctly your TB blade should open, if it is closing, reverse terminals on battery and try again.

return aux 9 and 10 back to vipec plug but this time with correct polarity.

delete errors

that should do the trick

Just to clarify, the wires to the E-throttle motor should be touched to the battery terminals, not the Aux 9 and 10 outputs of the ECU.

Scott. 

[josey]

Just to clarify, the wires to the E-throttle motor should be touched to the battery terminals, not the Aux 9 and 10 outputs of the ECU.

Scott. 

yes

sorry if i was unclear

 

 

[S4-VR6]

Scott,

I have verified the voltage for the TB motor, this did not solve the problem, it just drives the TB into the closed seat.  One interesting thing I found was that the Pin out for Aux9 and 10 seemed to be wrong.  I am getting +12V on what the pin out drawing calls Aux 10 (purple/white wire) and 0V on Aux9 (Purple wire) I just figured it was an error in the pinout drawing due to the fact that I cannot select which channel is positive voltage or common. I currently have it wired so that the measured +12V pin form the V88 opens the TB when the key is turned on.

another observation I had was that when I disconnect the +5V excitation voltage from the potentiometer I get the same result.

Is it normal to get the same ECU fault code when the Aux9/10 channels are disabled?  

What drives the E-Throttle “current target position”, I am guessing it is the FPS which is at full closed when the key is turned on? Is there some way I can change it? Could something else like the active e-throttle table be taking control?

How do I change from closed loop to open loop control?

Why, if at initialization it is being told to go to 100% open (in the case it was wired backwards), is it tripping on over temp/overcurrent knowing that I am getting analog voltage position feedback into the runtime value window (and it changes with manual movement of the TB)? Shouldn’t it be able to hold the TB wide open for an extended period of time?

It seems to me that the V88 is not modulating the control voltage to the TB motor because I have analog voltage from my FPS, and analog voltage from the TPS (although the TP main % position is 0 while the sub is 100% in the runtime values window, if I move the TB by hand the sub goes to 0 and the main does not change, stays at 0, but the analog voltage does just not the % feedback value). This all happens after I get the ECU fault code 84 so I am not sure if this active fault is causing things to go into a “safe” mode.

I will play with the target value to see if that makes any difference.

 

Thanks!

[Scott]

Hi Bob,

I believe Simon has replied to you via email.

Scott.

[josey]

did you switch positions on aux 9 and aux 10?

 

 

[Simon]

Found a number of configuration issues around the ethrottle. Main one being the target table configuration.

 

[S4-VR6]

As Simon Stated, 

The main issue was the target table. I also performed a firmware update which contained numerous stepper motor updates which did not hurt... all wiring is per the PIN out drawing and throttle body wiring diagram. I have good control of it but I am still getting the same two faults: [8:32:15 PM] ECU Fault Code 84: Aux9/10/E-Throttle IC Over-temp, [8:32:13 PM] ECU Fault Code 73: Aux 9/10 Supply Error. Not sure why

 

thanks,

Bob O

[Scott]

Hi Bob,

The code 84 usually occurs if the e-throttle motor is trying to drive the plate closed or open more than it physically is able to. I would re-do the TPS calibration process. You could also try reducing the Max Clamp and Min Clamp values, maybe try (+/- 80%).

Does code 73 occur at the same time as code 84? If yes then I believe it is caused by the ECU disconnecting the e-throttle power supply to protect the IC from over-temp damage. If code 73 occurs at a different time then check the power supply to pin B5, and also the control of the e-throttle relay.

Scott

[S4-VR6]

Scott,

When the throttle was being driven into the seat, prior to getting the target table sorted, those faults make sense. I will double check to make sure that it is still not being driven into its seat but I am pretty sure at closed position (the position where the fault occurs) the TB is at 2% open and following the set point within the target table. The two codes always seem to occur within a second of each other. The throttle continues to work after the codes appear, could this indicate a false positive?  

I had another issue spring up on me this weekend. I changed my throttle body plug with one that had the mechanical locking clip in tack (the original plug was missing this and I was afraid it would fall out) and when I plugged it back in to test it I got an volt 3 and 4 error, below the set threshold. These are the channels I have set for my TPS main and sub. I know why I have an volt 1 and 2 errors but this is the first time I have seen this fault on 3 and 4. any ideas why a new plug would bring out these faults? see attached.

I also still cannot perform a MAP calibration because my runtime values are outside the acceptable limits to be able to perform the cal, any idea how to get around this?

 

Thanks,

Bob O

        

[Scott]

Hi Bob,

All I can think is that the new plug has increased or reduced resistance compared to what the old one had. Re-doing the TP Calibration process should take care of any change. 

Looking back through the messages you have sent us I can see you have upgraded the firmware, which version are you on now? Quite a while back we had a firmware problem where a fault code could be incorrectly reported. If your e-throttle motor continues to function after you get the code 84 and code 73 then either our firmware is possibly not behaving correctly. Are you able to send me a PCLog of the error messages happening, and the base-map being used?

With the key-on and engine off what does PCLink report your MAP and BAP as? If you email me your base-map and the calibration data for the sensor I can confirm it is entered correctly.

Regards,
Scott