**NEW** Torque Pro CUSTOM PIDs- Reverse Eng'd Steering Wheel Angle & Front Wheel Turn Angle

Hello

Im not sure if there have been any threads related, i search 2nd gen and could not find anyone posting info regarding PIDs related to Steering column sensor and front wheel turn angle (equation formula for the later is dependent on the ratio of your specific vehicles steering rack pinion ratio) ( be aware there may be different steering rack ratios between models due to wheel base or other factors, i dont know)

you know how nice it would to be able to do home alignment using this where for caster all you have to do is have a person hold the wheel to the targeted turn angles displayed on torque pro to do the left and right caster angle measurements using the camber gauge without having to have a protractor on the ground to determine if your turned to the proper angle left or right ???
(friendly remember that any wheel turned away front the centerline will show a more negative camber than when pointed straight and any wheel pointed towards centerline will show a more positive camber than your pointed straight camber reading thus depending on which angle you chose to do a left vs right turn camber test, you do the math on the camber measurements to determine the caster amount

For my 2015 DCSB PreRunner Offroad edition
(my steering rack factory pinion ratio is i believe to be 19.4:1)

i played with custom PID settings in Torque Pro and came up with what i think works for monitoring Steering Wheel Angle (+/- 1080 degrees)(enough for 3 full turns either way, not that itl'l go that far, but in case your sensor is off or fails, its nice to have a wider window than normal) and then Front Wheels Turn Angle (+/- 35 degrees (mine goes to about 33)) depending on your steering rack pinion ratio (i believe my steering rack from the factory is 19.4:1 but i have not verified this)
If my rack ratio is that, it would mean for every 360 degree turn of the wheel my front wheels turn 18.556 degrees (again this is unconfirmed because i havent put it on turn plates to check the turn angle against a protractor, if someone could do this, it would be great)(or if anyone knows the factory steering rack ratio(s) for sure, please post it or them, if more than one rack ratio exists for the 2nd gens)

***ACCURACY is UNVERIFIED*** The gauge readouts on my truck are responding and throwing values so the data for these PIDS are there and are responding raw canbus data being spit out from the module receiving signal from the steering sensor, its just that the math equation to convert the PIDs are yet to be verified.
I just plugged in the custom PID values today and during a quick rough eyeball test, when i turn center the wheel it shows 0 when i turn left 180, it reads -180, when i turn right 180 it reads 180 same for when i turn the steering wheel a full turn to 360 or turn and a half to 540 or two full to 720 both left and right look good via the eyeball method so far. and positive an negative sign of the values are accurate.

As far as the front wheels and using my suspected rack ratio of 19.4, it looks like 15 or 30 when i turn left or right and just eyeball the wheels to those angles as compared to straight. again, i need to get a protector test or have someone with alignment turntables put their front wheels on them and then turn them and cross check the protractor angles on the turn tables against the second custom PID equation. i dont own any turn tables but if i have to, ill chalk some lines on the ground and check them with a old school angle protractor when i have time to get around to it.

STEERING WHEEL COLUMN SENSOR ANGLE:

ODB2 PID editor
2106
Long Name
Steering Wheel Column Angle Sensor
Short Name
STEER WHEEL
Minimum value
-1080
Maximum value
1080
Scale factor
x1
Unit type
ANGLE
Equation
(((C+(B*256))-32768)*0.1)
ODB Header
7B0
Diagnostic start command
(leave blank)
Diagnostic stop command
(leave blank)
Overrides PID
"does not override any PID"
Remember equation function data:
"do not store value" or (choose a setting as required by your needs)

FRONT WHEELS TURN ANGLE: (equation is based on 19.4:1 rack, change equation to divide by your rack ratio if needed)

ODB2 PID editor
2106
Long Name
Front Wheels Turn Angle
Short Name
FRONT WHEELS
Minimum value
-35
Maximum value
35
Scale factor
x1
Unit type
TURN ANGLE
Equation
((((C+(B*256))-32768)*0.1)/19.4
ODB Header
7B0
Diagnostic start command
(leave blank)
Diagnostic stop command
(leave blank)
Overrides PID
"does not override any PID"
Remember equation function data:
"do not store value" or (choose a setting as required by your needs)



NOTE: For both custom PIDS above, the ODB Header MUST be 7B0

This is extremely important BECAUSE if you leave blank then it will default look at 7E0 which is the engine ECU and you'll be getting PID 2106 from the wrong unit

i have no idea what's on the ECU module (7E0) at PID 2106 ... but 7B0 gets the info from the correct module.

Enjoy

and feedback and contributing updates or new findings will be appreciated by all so we can help each other

 

Hello all, Since i added these PIDs i have found something concerning. looking to see if anyone can provide insights to.

I had my 2015 tacoma parked, engine off with the steering wheel turned left

i disconnected my battery for a while to do some work and when i reconnected the battery, the steering wheel sensor zeroed out to the position of the wheel was turned to. which happened to be turned left over 360 degrees.

so i decided to drive and see if it stayed biased showing a left turn while driving straight and sure enough it did....my gauge was showing the wheel was turned left 400 degrees and if i stopped and did a lock to lock test full left then full right, it was indicating it biased 400 degrees towards a left turn.

i didnt immediately equate this to having changed due to the battery disconnected/reconnected. initially i just thought somehow the calibration slipped or changed for whatever reason so i decided to perform the VSC calibration test with the jumper wire method at the odbii connector and recalibrated everything.

drove the vehicle, everything showed lined up again

then it hit me that maybe the sensor recalibrates its zero to the ecu anytime the battery is reconnected. so, out of curiosity, i decided to park it again with the wheel off center and this time turned the other direction , and then i unplugged the battery and waited 10 seconds then reconnected to see if it would happen again. it did... again the ECU zeroed the sensor to where the steering wheel was physically at at the time of battery reconnect

so this time, instead of doing the vsc calibration, i decided to center the wheel and then unhook, wait then reconnect the battery back and sure enough the sensors in the column when back to zero .

so i have determined that the ECU, when powered up after a battery being disconnected, then reads the steering angle sensor and sets it to zero at wherever you have the steering wheel turned to.

So...in light of this....does anyone know if the vsc calibration is also performed at battery reconnect? because if it is not but the wheel takes on a new zero, then my concern is my VSC would not be working correct

first, i dont want to drive it mis-aligned to find out the hard way should it behave funny at 60+ mph because i have heard of wild things happening to peoples trucks when driving with the vsc cal not matching the steering angle

second, for now.... i am making sure that i center my wheel anytime i need to unhook the battery so next time i reconnect it. my steering angle sensor is still zero when wheel is zero and figured its worth mentioning this to others to do the same until maybe someone here can inform.

regardless if you have ability to read the angles like i now can or not. i think we need to find this out. without the added gauge, i would have never known and maybe this is why some people are having funny things happen with vsc trying to function when they were driving straight. ive read one thread on here where a guy claimed his truck "tried to kill him" because vsc was firing individual corner brakes while he was driving straight

just wondering if anyone knows if the VSC is automatically recalibrated to match the steering angle sensor if the battery is connected with the wheels not centered or does the wheel take on a new zero but the VSC isnt matched to it ????

for sure i can confirm that the steering wheel sensor input to the ECU takes on the current steerting wheel position as the new zero each time battery is reconnected,

BUT..... does the VSC do same to keep in in cal ???????

since most people dont have a gauge and likely would have ever seen this

also, is there any documentation to inform to center the wheel before reconnecting the main battery anytime you've had to disconnect it?

 

I have previously investigated a couple of aspects of your question above and I can tell you that the continuous reading of the angle sensor is taken into account by the VSC and other systems that use it. In other words, you are not suddenly discovering some massive flaw in Toyota's engineering or implementation of the VSC and other systems - they use rate of change and relative position of the steering angle sensor, not the absolute position.