Steering issue under braking !

[amirnew]

Originally Posted by Nmstec

The module itself simply allows the power steering system to operate under whatever conditions you like. If you want to integrate it back into the the same car (like the BRZ and redreplicant did), I allow that, and will supply you with custom firmware that gets rid of the EPS light.

Control can be done in whatever method you like, potentiometer, canbus control, canbus VSS map, anything you can think of.

The peak current is not done by my controller, it is done directly with the OEM steering system when you do a fast input (high torque, high assist). You can simply dial down the assist with my controller, that in turn will also produce a lower current peak during fast inputs.

Your system replaces the oem eps unit?
Is there anyway just to lower the entire electric power asist level? Like adding resistors on the torque sensors inputs or something like that.
Does the loss of eps assist comes from the motor itself or the eps control module input voltage drop because of the wiring to the unit are thin and the high demand causes voltage drop on the unit's power input

[Nmstec]

Originally Posted by amirnew

Your system replaces the oem eps unit?
Is there anyway just to lower the entire electric power asist level? Like adding resistors on the torque sensors inputs or something like that.
Does the loss of eps assist comes from the motor itself or the eps control module input voltage drop because of the wiring to the unit are thin and the high demand causes voltage drop on the unit's power input

My module does not replace the OEM controller. It simply takes control of it, pretending to be the rest of the vehicle.

Please do not ever do any modifications to the torque sensors, theres countless OEM problems with torque sensor failing and car going full bore to one side.

For the loss itself, we are still investigating. We are guessing its either temperature on the mosfets (The oem mosfets appear to massively deteriorate almost linearly with temperature), or its a simple matter of overcurrent protection. We have confirmed that dropping the assist level with my controller does appear to ward off the dreaded cut-out significantly, but not all the way.

[ML]

Originally Posted by Nmstec

My module does not replace the OEM controller. It simply takes control of it, pretending to be the rest of the vehicle.

Please do not ever do any modifications to the torque sensors, theres countless OEM problems with torque sensor failing and car going full bore to one side.

For the loss itself, we are still investigating. We are guessing its either temperature on the mosfets (The oem mosfets appear to massively deteriorate almost linearly with temperature), or its a simple matter of overcurrent protection. We have confirmed that dropping the assist level with my controller does appear to ward off the dreaded cut-out significantly, but not all the way.

have you tried heatsinks on the mosfets?

[amirnew]

Originally Posted by Nmstec

My module does not replace the OEM controller. It simply takes control of it, pretending to be the rest of the vehicle.

Please do not ever do any modifications to the torque sensors, theres countless OEM problems with torque sensor failing and car going full bore to one side.

For the loss itself, we are still investigating. We are guessing its either temperature on the mosfets (The oem mosfets appear to massively deteriorate almost linearly with temperature), or its a simple matter of overcurrent protection. We have confirmed that dropping the assist level with my controller does appear to ward off the dreaded cut-out significantly, but not all the way.

Meaning that even with your ecu the steering assist loss is still present even when dialing back the assist level?

Are you sure it isn't issue with the high current inrush that causes the eps ecu input drop in voltage and causes reset?
You're made sure there is at least lets say 12v at the ecu input when the protection\cut off\reset kicks in?
Will be really glad to try and help you, help us solve this issue.
I'm electrical engineer and have access to some pretty cutting edge technology development analog guys and if I'll have more data like schematics, measurements anything maybe we can figure it out together.

[Nmstec]

Originally Posted by ML

have you tried heatsinks on the mosfets?

The entire back 1.5 inch thick case is the heatsink in this case. We recently found (RedReplicant and a few others who run column modules) that it seems there is indeed a current limit cutoff controlled by the MCU itself. On the prius columns one of our common friends had simply lowered the resistance of a current shunt, and his problems are all gone!

[amirnew]

Originally Posted by Nmstec

The entire back 1.5 inch thick case is the heatsink in this case. We recently found (RedReplicant and a few others who run column modules) that it seems there is indeed a current limit cutoff controlled by the MCU itself. On the prius columns one of our common friends had simply lowered the resistance of a current shunt, and his problems are all gone!

Can we somehow donate or something for your test of this theory in the brz gt86 mcu module?
Or you can sell the shunts + schematics\instructions of how to execute the replace and where the shunt ia located.

This is really major fault with the car and i just can't understand how anyone with this car do not complain about this.

[Nmstec]

Originally Posted by amirnew

Can we somehow donate or something for your test of this theory in the brz gt86 mcu module?
Or you can sell the shunts + schematics\instructions of how to execute the replace and where the shunt ia located.

This is really major fault with the car and i just can't understand how anyone with this car do not complain about this.

I appreciate the offer, however RedReplicant and I have already a small plan to test it! He has the car, and I have a GT86 controller. I will do the modifications and will try it out on his car. I will keep you guys updated!

[amirnew]

Originally Posted by Nmstec

I appreciate the offer, however RedReplicant and I have already a small plan to test it! He has the car, and I have a GT86 controller. I will do the modifications and will try it out on his car. I will keep you guys updated!

Amazing! Appreciate it so much. Any improvement is welcome!
Thank you thank you thank you.

[jflogerzi]

Amazing guys! Keeping an eye on this.

[amirnew]

Originally Posted by Nmstec

I appreciate the offer, however RedReplicant and I have already a small plan to test it! He has the car, and I have a GT86 controller. I will do the modifications and will try it out on his car. I will keep you guys updated!

Do you have any time estimation?🤣

[RedReplicant]

Originally Posted by amirnew

Do you have any time estimation?��

I have two track days this weekend where I'll be trying a few things, but not the shunt change. Next events after that will be Feb 18/19.

I had my assist fixed to 40% at the last event and it still cut, but it was nowhere near as bad as with the stock controller.

[amirnew]

Originally Posted by RedReplicant

I have two track days this weekend where I'll be trying a few things, but not the shunt change. Next events after that will be Feb 18/19.

I had my assist fixed to 40% at the last event and it still cut, but it was nowhere near as bad as with the stock controller.

How did you fixed the assist level to 40%? With nmstec?
Why not tring the shunt first,seems like this will raise the current limit and prevent the cut off.
Do you have pictures of inside the eps ecu?
What correctly is the shunt value?

[RedReplicant]

Originally Posted by amirnew

How did you fixed the assist level to 40%? With nmstec?
Why not tring the shunt first,seems like this will raise the current limit and prevent the cut off.
Do you have pictures of inside the eps ecu?
What correctly is the shunt value?

1. With nmstec, yes. It is super easy to use via your phone - you can build your own assist map vs VSS (or others), set a flat assist rate, use a potentiometer, etc. I have mine wired so I can easily swap between the stock CAN and the nmstec CAN control with a DTM connector. It is also wired into the chassis CAN so my EPAS light isn't on.

2. I put the nmstec into the car a few months ago, this shunt stuff was found out about in the last week. Also, I am not entirely sure what kind of fun failures the shunt change could introduce and I am trying to keep the number of changes at a time down so we actually know what made a difference.

3/4. I don't, nmstec may

[amirnew]

Originally Posted by RedReplicant

1. With nmstec, yes. It is super easy to use via your phone - you can build your own assist map vs VSS (or others), set a flat assist rate, use a potentiometer, etc. I have mine wired so I can easily swap between the stock CAN and the nmstec CAN control with a DTM connector. It is also wired into the chassis CAN so my EPAS light isn't on.

2. I put the nmstec into the car a few months ago, this shunt stuff was found out about in the last week. Also, I am not entirely sure what kind of fun failures the shunt change could introduce and I am trying to keep the number of changes at a time down so we actually know what made a difference.

3/4. I don't, nmstec may

So... How was the weekend 😄