wtf is a c1234?

[jamesm]

got my flex fuel setup installed... out doing some WOT runs getting it all dialed in. it's all going very well until ~20psi, when i run into two problems:

- the grimmspeed ebcs is maxing duty cycle trying to hold boost above 6k or so with the 7psi spring in my turbosmart gate. annoying, but i can fix that.

- i can't get the damn car to hook up through a whole 3rd gear run from 2.5k to redline. everytime it spools it just spins. fun, but kinda makes tuning a bit difficult. even 4th gear kinda skitches around through the peak torque area spinning quite a bit. time for something better than cheap kumhos, i guess.

anyway, so while i was playing with the wg tables trying to see if i could eek out a bit more boost out up top, i was doing a wot run and my cluster lit up with the abs light and traction control lights. it had been spinning all the way through 3rd again, but this hadn't happened before.

i pulled over and checked for codes and found code 'C1234' in the ABS module. ecutek docs don't even reference this, and a google search is pretty inconclusive. has anyone experienced this, or does anyone know what this code references on our cars? i cleared it and it didn't come back, but i haven't done another run since....

[steve99]

Yaw rate sensor malfunction, you weren't doing donuts were you ??

http://share.qclt.com/%E4%B8%B0%E7%9...em/0370019.pdf

Yep is a RAV4 buy it's a toyota.

I'll try the BRZ workshop manual when I get home

[jamesm]

Originally Posted by steve99

Yaw rate sensor malfunction, you weren't doing donuts were you ??

http://share.qclt.com/%E4%B8%B0%E7%9...em/0370019.pdf

Yep is a RAV4 buy it's a toyota.

I'll try the BRZ workshop manual when I get home

yeah i saw that but wasn't sure if it was applicable as it didn't make much sense given the context. i hadn't done any donuts or anything... just straight-line power pulls, 2.5k to redline. it may have kicked sideways a bit but not much.

[AZFA20]

I had that pop up once too and never really figured it out so I finally just cleared it and have never been able to reproduce it since.

[OmarGC]

C1234: excessive hoonage detected--if vehicle is not modified, clear codes and immediately void warranty.

[steve99]

Originally Posted by jamesm

got my flex fuel setup installed... out doing some WOT runs getting it all dialed in. it's all going very well until ~20psi, when i run into two problems:



- i can't get the damn car to hook up through a whole 3rd gear run from 2.5k to redline. everytime it spools it just spins. fun, but kinda makes tuning a bit difficult. even 4th gear kinda skitches around through the peak torque area spinning quite a bit. time for something better than cheap kumhos, i guess.


i pulled over and checked for codes and found code 'C1234' in the ABS module. ecutek docs don't even reference this, and a google search is pretty inconclusive. has anyone experienced this, or does anyone know what this code references on our cars? i cleared it and it didn't come back, but i haven't done another run since....

Ok looked in BRZ repair manual Definitely

DTC C1234 Yaw rate sensor error

If there is a malfunction in the yaw rate sensor which is integrated into the skid control computer (brake actuator ASSY), the skid control computer (brake actuator ASSY) outputs a diagnostic code and prohibits the Vehicle stability control operation for fail safe.

Diagnostic codes
DTC detecting conditions
Faulty part
C1234
Skid control computer (brake actuator ASSY) internal error (yaw rate sensor)
Skid control computer (brake actuator ASSY)
C1419
Skid control computer (brake actuator ASSY) internal error (G sensor)
C1472
Skid control computer (brake actuator ASSY) internal error (lateral G sensor)
C1474
Skid control computer (brake actuator ASSY) internal error (longitudinal G sensor)


Recommends checking wheel speed sensors for damage or foreign material

Check speed sensor with techstream (think you have that) should be equal

1. VDC sensor midpoint setting mode
CAUTION: ·When the skid control computer (brake actuator ASSY) has been replaced, make sure to perform VDC sensor midpoint setting.
·Make sure to perform [VDC sensor midpoint setting mode] on a level surface (grade of 1 % or less). While centering, do not shake the vehicle or open/close a door.



NOTE: When performing [VDC sensor midpoint setting mode], make sure to set zero point of yaw rate sensor & G sensor (brake actuator ASSY is integrated) and steering sensor.


(1) Turn the ignition switch to OFF.

(2) Shift into neutral and apply the parking brake.

(3) Connect the SSM3 to the DLC3.

(4) Turn the ignition switch to ON.

(5) Set the steering wheel in a straight position.

(6) On the SSM3 screen, select [ABS/VDC System]→[Work Support]→[VDC sensor midpoint setting mode].

(7) Following the SSM3 screen, perform [VDC sensor midpoint setting mode].


2. Changing modes
·When it is necessary to temporarily stop the control while operating the vehicle on a device such as free rollers, enter into the check mode. While in the check mode, DTCs listed in the list may be stored.
·If any DTCs are stored, clear the DTCs using SSM3. After turning IG OFF→ON, the conditions are normal if speed sensor related DTCs are not stored.

Code list
Code no.
[SAE]
Content of diagnosis
C1271
FR wheel speed sensor signal, lost
C1272
FL wheel speed sensor signal, lost
C1273
RR wheel speed sensor signal, lost
C1274
RL wheel speed sensor signal, lost
C1275
FR wheel speed sensor signal error
C1276
FL wheel speed sensor signal error
C1277
RR wheel speed sensor signal error
C1278
RL wheel speed sensor signal error




I reckon its just confused as vehicle accelerated outside its normal operating range. Your not running a staggered tyre setup with different diameter tyres ??

If you want mre let me know , will try and find download link for manual again

[brn12345]

Could also be caused by excessive wheel spin overwhelming the lsd resulting in high differential rear tire speeds, this coupled with the fact that the rears are spinning faster than the front could trigger logic in the ecu. Theoretical but possible.

Having said that, I get the cluster to light up like you described everytime the car is on the dyno or during burnouts at the dragstrip. Never really found out why my car does it as other cars (BRZ/86) don't usually do.

[steve99]

Originally Posted by brn12345

Could also be caused by excessive wheel spin overwhelming the lsd resulting in high differential rear tire speeds, this coupled with the fact that the rears are spinning faster than the front could trigger logic in the ecu. Theoretical but possible.

Having said that, I get the cluster to light up like you described everytime the car is on the dyno or during burnouts at the dragstrip. Never really found out why my car does it as other cars (BRZ/86) don't usually do.

With the kind of horsepower i imagine jamesm is putting out with 20psi boost on E85 i reckon the standard traction stability program wont know what day of the week it is let alone how to control it. i am not supprised it gave up and blamed its own sensors




A guy over here reckons even if the stability and traction are switched off it kicks back in at speeds over 140 kmh if the car gets out of shape.

Do the other cars have same rom revision numbers as yours

[Deadspool]

I am also consistently getting wheel speed codes while hooning.

[DriftHappens]

I don't....maybe i need MOAR SIDEWAYZ!

[Luckrider]

@jamesm, when are you going to finally get this car on a dyno? I would love to see what the torque curve looks like and what sort of numbers you are putting down. You need new tires first

[jamesm]

Originally Posted by Luckrider

@jamesm, when are you going to finally get this car on a dyno? I would love to see what the torque curve looks like and what sort of numbers you are putting down. You need new tires first

Just did today . Dyno'd at 11psi and 15psi on e66. Made 344/387. Wastegate won't allow holding higher boost to redline, so I've dialed it back until a new spring comes in.

[Luckrider]

What is your boost threshold?

[jamesm]

Originally Posted by Luckrider

What is your boost threshold?

it'll spool whatever i want (up to 22+ psi) but it quickly tapers back off to 15 psi by redline. on the dyno it hit 16.5ish and tapered back down to 15. the first run was 11psi solid to redline.

here's a vid:

[ame="http://www.youtube.com/watch?v=k6Ty_5kdBRU"]http://www.youtube.com/watch?v=k6Ty_5kdBRU[/ame]