Guys, I've searched and only found sideways references to this. Is there a re-learn process for the variable effort steering in a 2005 Manual Base Coupe when the steering rack is replaced?

The problem is, especially at low speed, the steering is a bunch heavier than with the old rack (I swapped the rack since I had it out when I did the balancer). I took it to the dealer to do the relearn, and the tech couldn't get the computers to talk to his tool. I got a VX DIAG and did get the EBCM to talk after cleaning some grounds. I can see that it says it's commanding ~-2A, and doesn't fail it, but the steering is still heavy. I also can't see an option in Tech2Win for relearn etc. of the VES. Any ideas? Am I chasing the wrong thing?

Thanks,
Bill

 

Tech 2 win,
North America from the pop up screen,
mdi 1 from the pop up screen
USB device from the pop up screen
Note,if you don't get these pop up screens once you start Tech2win, your OS is not correct for the program, hence not win 7.

Tech II main screen enter,
Diagnostics enter
2005 enter
Passenger car enter
Chevrolet enter
Y enter
Steering enter
Varible effort steering
ECBM enter
steering position test enter
Run thought the sensor test using the continue button and mouse button pushes. This will calibrate the ECBM for the steering wheel sensor, for the Variable Effort Steering Re-Learn Process Side to side locks, and centered portion).

Also, it helps before the above step since you did replace the rack, to put the car into run mode-motor off with a 10 amp charger on the battery, go into steering wheel and column from the above steering menu instead, data display and make sure that your steering wheel sensor is reading 0 with the steering wheel an front tires straights, and the position goes to positive values where you turn the wheel right, negative values when the turn the wheel left.

If you are at either major positive or negative values with the steering wheel straight and the front tires straight ahead (not at 0 or slightly off it either way), then the steering column is rotated one full rotation to the steering rack out of index, and you will need to unbolt the column coupling with the front wheels straight, turn the steering wheel to zero out the steering sensor to O with it straight, and re-bolt the steering coupling back to the rack spindle shaft.

Again, turning the wheel to the right will increase the value on the positive side from O, while turning the wheel to the left will increase the value to on the Negitive side from O. So do not rotate the steering wheel two full turns past Zero either way, or you will screw up the steering wheel sensor. Hence above steering wheel calibration test will only work with the Steering wheel sensor reading zero with the wheel straight, the tires aim straight, and the sensor changing readings as the wheel is turned.

Also, if you dinked around with the brake pedal and need to re calibrate the brake pedal sensor while your at it,

steering enter
Steering wheel and column enter
Module set up enter
BCM enter
BPP sensor calibration enter.
Follow the menu directions using the mouse to push the White continue button middle bottom on the screen (not the arrow pad to the right).


As for the VES programming, it part of the ECBM programing file, and you will not have any control over it's effects (unless you have the tallent to write a new Firmware program to give different values isntead). All you can do is make sure that the ecmb is reading/calibrated the Steering wheel position sensor from lock to lock positions, the sensor reading O at the wheel and tires straight. With the VES connector connected to the steering rack, changes the elect field of the Magnasteer instead. Also, make sure that your tires are the correct size, or adjusted in the tune if not stock sizes so the car is reading the correct MPH as well (part of the VES system as well).

Read to understand how the VSS/Magnasteer works on the vet,
https://www.corvetteforum.com/forums...-steering.html


If the EBCM was replaced, then it may need to be firmware flashed with the correct File for your 2005 vet.
This can be done with a TDS SP subscription for $40 for 2 years per car vin number.

 

Thanks, Dano! I'll give this a try once my son heads to bed tonight. Do you suggest putting it up on stands for this? (I'd think so, but you see how far I got without help so far)

 

Just need to get the front wheel off the ground, since you will have the car in run mode-motor off (press the bottom of the starter button in for 5 seconds) and a 10 amp battery charger on the battery so the battery does not get drained down with you using the Tech II, the modules all light up, and the motor not running to recharge the battery.


If you think that you can turn the steering wheel all the way left and then all the way right with no power steering, the wheel still in contact to the ground, then front tires do not need to be pulled off the ground.

Also double check the steering wheel sensor read out with the tires and steering wheel straight to begin with. It too easy to get the column one rotation of index when you have doing the steering rack replacement. Hence before you install the coupling to begin with, check the steering wheel sensor to make sure it reading 0 to start with instead.

If I had to bet on the problem, would dare to guess when you go to check the steering wheel sensor, it's no where near Zero, and the steering column shaft is indexed one rotation in the wrong way instead.

If the steering wheel sensor is not changing its reading as you are turning the wheel, you did not clip the sensor back in/up when you installed the coupling.

 

Ok, your last sentence caught my eye there, since the steering angle reading is stuck on zero in the data readout even though I can get a "Passed" readout from the test in the Tech II. Where would I unhook the steering sensor around the column? I don't recall undoing any wires other than the harness on the rack, which I reconnected, though there may have been something else I forgot.

​​

 

Bottom plate of the steering wheel sensor can snap out, or the plug connector can get unplugged for it.

https://www.corvetteforum.com/forums...g-message.html

The other side of the cabling goes to the EBCM connector, so if you have problems on the EBCM side, then disconnect the ECBM connector, clean it and the pins on the EBCM socket with spray contact cleaner, and see if that solves the problem.

As for passed test, do you mean that the steering position test passed without problems, hence left to lock, right to lock came back without problems? If so, then EBCM is seeing the senor without problems, but the BCM is not sending back the information to the Tech II.

If the above is yes, steering position test passed, start the car, go into BCM data display and see if your getting a change in the Steering position values in those tables when you are moving the steering wheel side to side instead.

 

Short of the above, really need to check the pump for flow rate and pressure through the rack (you did power bleed the rack correctly to get all the air out of it, hence motor running so the pump is pumping, then full left to lock, full right to lock and back and forth a few times more to burp any out of the lines).

Test the VSS connection for power,

and if the both the above check out, then could be a bad steering rack instead.

 

Well, I'm having problems talking to the modules again. I cleaned the EBCM connector, the ground for the EBCM (G105), the ones from the battery on the block (G106) and frame (G104), and the one for the OBD II port (G201). In a strange event, I was still getting comm from a few things (like the HUD, driver's door module, etc) with the tool connected and G201 undone. Is that an indication of a short somewhere? Right now, I can't get the BCM, ECU, and EBCM to talk through the VX DIAG. From what Dano said 2 posts ago, it seems that a bad BCM connection could cause other modules to not talk, so I'll try to clean the ground for that next, but is there something else I should be checking? I'm starting to get stumped. Thanks for all the help so far, Dano; and anyone else feel free to chime in.

V/R
Bill

 

OBDII port goes directly to the BCM.

So start by cleaning the OBDII port connectors and if you still have problem, remove the positive battery cable connector from the batttery, then pull the two Blue and the single red connector on the BCM to give these connectors and BCM socket pins a good cleaning as well.

Also, pull the large 20amp fuse on the BCM dead center of all the fuses (it's the fuse for the GM land bus) to clean it's legs and the socket clips pins as well.

If you still have problem with the BCM not communication on the OBDII port, we need to pull the BCM board to make sure it not the problem. Hence if the A/C air box drain pipe got clogged, instead of the collected water draining out the drain hose to the outside of the car, the water will collect in the air box to dump to the BCM instead.


So to get the board out of the BCM case, you will drill the top of silver sleeve rolled edges of both studs, while will allow the case to be snapped apart to pull the board. The board is given a good spray electrical cleaning, check for any corrosion, as well as any bad cold solder joints that need to be re soldered as well.


Now with communication from the ObdII port to the BCM, if the BCM can not communicate with the ECBM, then the ECBM connector is pulled, it and the socket pins cleaned, connector re-connector, and check again. Still problems, then the EBCM board is pulled like the BCM board, its cleaned and check for cold solder joint problems as well.




As for taking the car to a dealer, they will not pull any modules apart to check the boards, but will just want to replace the modules instead, including the cost to SPS firmware flash the new module as well.

 

Thanks once again, Dano! Between work and having a 4 year old, that should keep me occupied for about a week worth of spare moments. I'll make sure to let you and any lurkers know how it turned out.

No shame, lurkers, it's how you (and I in most cases) learn.

 

OK, I got out there tonight. First I cleaned the all the stuff on the BCM (2 big blue/gray plugs, big red/black screw in plug, and the 20A GMLAN fuse) then I pulled the trim and cleaned the ground in that side for good measure. That seems to have cleared up the Comm problems as I was able to see all the modules now.

I went into the data display and the first time, the steering angle sensor was giving me a reading. I then did the sensor test and got a failure. I decided to try again, turning the wheel faster and got a pass. After that I went in to double check the angle reading and it was stuck on zero again. Nothing I did for the rest of the night changed that, motor on, motor off, I restarted all the software a few times, still zero.

I pulled the trim panel under the wheel to get at the sensor. It seems to be in place. The harness has the "comb" thing that was the solution to keep it from coming loose on a particular TSB for 05s. I wasn't in the mood to be upside down under the dash (I need to get to bed for work tomorrow soon), so I think my next step will be to clean the contacts for the steering angle sensor as well as the ones on the rack itself (this slipped my mind when I was under there this weekend). We'll see where that gets me unless anyone has any other suggestions.

Thanks for all the help so far!
V/R
Bill

 

Your on the right track, but add pulling the EBCM connector and cleaning it as well.

You do have the room to flip the EBCM lock lever and remove the connector without having to remove the EBCM from it mounts, so take your time (do a little swearing) and see if these three cleaning solve the problem.

 

Cleaned the plug on the steering position sensor and still getting zeros. I'm wondering if there's a way to check if the sensor is getting power at all? Also, could it be the big plug upstream from it?

This kills me because I got a reasonable reading that one time after I cleaned the BCM connectors which makes me think the sensor itself is OK.

 

EBCM is seeing the steering wheel sensor since you passed the steering wheel postion test, but BCM is not seeing it isntead.


As stated, pull the EBCM connector, clean the connector and socket pins and put the EBCM connector back on to see if that solves the problem.

With the EBCM cam lever unlocked, you have just enough room to remove the connector without having to unbolt the EBCM for it bracket. It's tight, but doable.

The ECBM socket pins are easy enough to clean with it bolted in place since you can get a good shot of spray in the socket to clean the pins.


As the EBCM connector you can aim upwards to give the connector pin clips a good shot as well.

EBCM and other end connector diagrams if you need them

http://www.mediafire.com/file/q6sddm...connectors.pdf

Hence steering sensor connector to EBCM connector wiring, terminates on the EBCM connector pins B13, B14, C6, C7 so you know what to really focus on when you are cleaning pins.

 

Ok, I cleaned all of these. Still no angle reading. I went into the VSES data screen to see if I could get raw sensor readings, and I do, both signal A and B move smoothly and logically with the wheel, but the angle reading remains 0. It also says "No" to the "Is Steering Centered" field. Now, here is where I'm wondering if I've made an error; do I need to drive the car and have it compare a speed and yaw sensor reading to "center" the steering? I've been doing all of this with the front of the car up in the garage and may have been missing that piece of self-generated feedback.

That said, we're sitting through Alberto coming ashore today, so I don't think they'll be a test drive until later this week.

 

To close the loop on this, yes, the steering angle sensor will stop centering after some time without moving the car so it can get credible signals from the yaw and speed sensors. I drove the car and got the sensor readings to work again. I also drove it with the tool hooked up, and the current signal to the VES seemed to vary in a logical manner with speed. I'd say it's fixed, though the steering has a bit more effort than the old rack.

Thanks for all the help, and I hope the thread can be a reference for someone else!