Steering angle sensor reset? Engine off or on?

[troutymouth]

- My AllDataDIY account says to turn the ignition to the "ON" position. It does not indicate if I should start it or not.
- I probably need to disconnect the battery for the spark plug + PCV change.
- It was just aligned, and reset, and the steering is so perfect. It drives straight as an arrow.
- My CX-7, before I traded it in, had a lot of trouble with this reset (the TCM light would go off far before I finished the turn left + turn right). It had several steering concerns that the dealer would not acknowledge. I don't want to mess this car up.
- I noticed a big difference on the CX-7 if I did the angle sensor initialization with the engine on and when I did it with the engine off. I am not sure which was right.

My thoughts/questions
- Should the engine be running for the angle sensor initialization?
- If I am scared of having to do this initialization is there a way around it? (Not disconnecting the battery, or using some kind of memory saver like this http://www.autobarn.net/xxxw-kas295a.html)

 

[ceric]

Wait.
Why do you need to do that?

The NAVI system (test mode) can show gyro degree (which is not steering angle), but
when your vehicle goes straight (like an arrow as you said) on a straight road, the gyro angle should
remain the same value (i.e. no change in momentum vector).

 

[troutymouth]

Wait.
Why do you need to do that?

The NAVI system (test mode) can show gyro degree (which is not steering angle), but
when your vehicle goes straight (like an arrow as you said) on a straight road, the gyro angle should
remain the same value (i.e. no change in momentum vector).

Whenever one disconnects the battery or the ROOM fuse, the steering angle sensor must be reinitialized. This is why the TCM light is on when you start the car for the first time after disconnecting the battery. If you don't do this right, several systems can be affected (Traction Control, VAPS, etc)

 

[ceric]

Got it.
How do you reinitialize it?

 

[pugsx]

Just think of how many cx9s who have gone to a non-dealer place to replace their battery. I doubt those places know about this sensor. Hmmmmmm.... This sounds.......off.

 

[troutymouth]

Just think of how many cx9s who have gone to a non-dealer place to replace their battery. I doubt those places know about this sensor. Hmmmmmm.... This sounds.......off.

I most certainly do not follow your logic here.

A simple google search would have been a better option before posting something so enlightening as "this sounds off" (eyeballs) . Just about every car with VAPS and TCS has some sort of reset procedure. This isn't anything new. I've owned 14 cars. Every one of them has had a steering angle sensor, or steering wheel position sensor. Not all had VAPS. For those with TCS and VAPS, not all makes require the same reset. Most don't store the calibration in memory that is erased each time the car looses power.

If you are in Arlington, I would suggest stopping by Currys, or Smokey's Garage and asking them to explain it to you. Just because you have never heard of it before, doesn't mean all the reputable folks never have.

Here is the service manual entry on the CX-9 sensor

• Inspect the wheel alignment, inflation pressure, and the installation condition of the steering wheel.
• If there is any malfunction, adjust the applicable part.
• Connect the negative battery cable.
• Turn the ignition switch to the ON position.
• Turn the steering wheel to full right lock, then turn it to full left lock.
• Turn the ignition switch to LOCK position.

If you go to a dealership and have your car aligned there, they will reset the steering angle sensor for you. My question was not if the sensor exists. It was not about if the procedure was required if the battery was disconnected. It was specifically and totally in regards to either avoiding having to perform the procedure or if I do - does the engine need to be on.

 

[table5511]

Trouty, I have seen dozens of technical service bulletins and service procedures (the service manual has also been posted on this forum) that involve disconnecting the battery, and none of them mention resetting the angle sensor. Now angle sensors are in the column and generally not on the p/s rack, and are used for roll stability control and those situations when the accellerometer in the vehicle senses an out of control situation, the computer takes the reading on the column to see where the steering wheel is at (what position). I know there are 2 schools of thought on steering wheel positions 1) after a proper good front end alignment, the steering wheel should be centered if all steering components are in good working order (i.e. no worn out parts), and 2) align the front end and then square the wheel (actually taking the steering wheel off the spline and centering the steering wheel).

In my experience, the steering wheel gets "squared" at sub par tire shops such as the large chain tire stores, but is not squared at more expensive places like dealerships, and local tire shops with actual knowledgeable staff and experienced technicians.

Now I don't know a ton about this, but I have asked around several places, and it seems like the consensus is that with good functioning parts that are not worn out, and proper front end alignment should result in a straight steering wheel without having to take the steering wheel off the spline.

What this means is that no calibration should be needed unless there are worn out tie rods, etc.

Just my 2 cents.... I could be wrong. In my line of work, I have paid a couple shops on some mercedes models to calibrate the steering angle sensor when replacing engine subframes and replacing certain suspension & steering parts, and this makes sense.

What procedure are you referring to that says to reset the sas?

 

[pugsx]

OK all you CX9 owners out there. Do NOT replace your battery yourself. Bring it to the dealer! Or else your car will not work properly. (whistle)

 

[table5511]

uh... to each his own.

 

[pugsx]

Whenever one disconnects the battery or the ROOM fuse, the steering angle sensor must be reinitialized. This is why the TCM light is on when you start the car for the first time after disconnecting the battery. If you don't do this right, several systems can be affected (Traction Control, VAPS, etc)

I'm feeling lucky today. I think I'm going to disconnect my battery and just reconnect it and live dangerously. Jokes aside, that is a bold statement above. I won't deny that there may be a possibility that this is true, logic tells me otherwise. If it is so important that this "procedure" be done, you'd expect this forum to have multiple post on or about the subject. You'd expect the owners manual to warn you not to disconnect your battery without the dealer's help. On this forum, there is none (as far as I can tell/search) except this very thread. Therefore, like Spoke, logic says you don't have to reinitialize the SAS whenever one disconnects the battery. I'm going to make an calculated guess that thousands of CX9 owners have disconnected their batteries and not had to do this procedure.

 

[Gunga]

For the uninformed, Just what is a Steering angle sensor.

 

[troutymouth]

I'm feeling lucky today. I think I'm going to disconnect my battery and just reconnect it and live dangerously. Jokes aside, that is a bold statement above. I won't deny that there may be a possibility that this is true, logic tells me otherwise. If it is so important that this "procedure" be done, you'd expect this forum to have multiple post on or about the subject. You'd expect the owners manual to warn you not to disconnect your battery without the dealer's help. On this forum, there is none (as far as I can tell/search) except this very thread. Therefore, like Spoke, logic says you don't have to reinitialize the SAS whenever one disconnects the battery. I'm going to make an calculated guess that thousands of CX9 owners have disconnected their batteries and not had to do this procedure.

Still not understanding your logic. You've basically stated that since several people don't know about something, it doesn't exist. You must know far more than the master tech who pointed this out to me in the first place.

Have you attempted to look outside the forum for this? A simple google search gets tons of results: Includes a list of cars where it is mandatory to reset the sensor after an alignment http://www.hunter.com/alignment/codelink/5549T.pdf

This is a nice one too: http://www.brakeandfrontend.com/Article/38832/Steering_P.aspx

I encourage you to give it a try. Pull the battery, hit the brake to clear everything. Hook it back up. You'll see your TCM light on or blinking, indicating you need to perform the procedure. You will run into the same question I posted, that I was hoping for an answer to. Engine on or engine off?

 

[pugsx]

Still not understanding your logic. You've basically stated that since several people don't know about something, it doesn't exist. You must know far more than the master tech who pointed this out to me in the first place.

Have you attempted to look outside the forum for this? A simple google search gets tons of results: Includes a list of cars where it is mandatory to reset the sensor after an alignment http://www.hunter.com/alignment/codelink/5549T.pdf

This is a nice one too: http://www.brakeandfrontend.com/Article/38832/Steering_P.aspx


I encourage you to give it a try. Pull the battery, hit the brake to clear everything. Hook it back up. You'll see your TCM light on or blinking, indicating you need to perform the procedure. You will run into the same question I posted, that I was hoping for an answer to. Engine on or engine off?

Well, the master tech didn't say engine on or off huh? : ) And I'm implying that if a lot of people do not experience a problem, then it might not be a problem.

I did not say alignment. All I said was disconnect battery. Why are you talking about alignment? I am challenging your statement about having to reset the SAS anytime you disconnect your battery.

I didn't say it does not exist. I eluded to the probability that since no one else with a CX9, on this forum, has experienced a similar problem that you might not have to do this thing just because you disconnected your battery. I didn't click on your links. Do they relate to a CX9?

Can you not see that apparently no on else is facing the stuff you are experiencing? I am willing to bet at least 10, no 20 people have disconnect their battery at some point of time since the CX9 was sold here. Do I see any post about the issues you are facing. No.

You made a bold statement. Can or would you like to back it up?

If anyone has disconnected their battery before, PLEASE post if you experienced what he is claiming. Until then, I stand my ground.

 

[pugsx]

Speaking of searches. http://www.mazdas247.com/forum/show...nnect-to-do-list&highlight=disconnect+battery

Last post mentions DSC light.
So 1 other person may have had a similar issue but that post said an event MAY occur and not WILL occur.

 

[ceric]

Here is the service manual entry on the CX-9 sensor

• Inspect the wheel alignment, inflation pressure, and the installation condition of the steering wheel.
• If there is any malfunction, adjust the applicable part.
• Connect the negative battery cable.
• Turn the ignition switch to the ON position.
• Turn the steering wheel to full right lock, then turn it to full left lock.
• Turn the ignition switch to LOCK position.

.

Just did some googling. Found a doc that says, SAS calibration is now required
for most 2010 vehicles after alignment or major repairs for damages to the steering.
That makes sense to me. It does not mention about battery disconnection, however.

http://www.google.com/url?sa=t&rct=...hLTjDw&usg=AFQjCNFsW72nUjsIK9B1Q_Mo4jMKqcwqIA

However, if calibration was done previously, after disconnecting battery, it might need to be recalibrated again
if such new settings/parameters are not store in ECU (don't know either way).
Just my two cents.

 

[troutymouth]

Well, the master tech didn't say engine on or off huh?

No obviously he didn't, or I don't recall. That was the initial question.

Can you not see that apparently no on else is facing the stuff you are experiencing? I am willing to bet at least 10, no 20 people have disconnect their battery at some point of time since the CX9 was sold here. Do I see any post about the issues you are facing. No.

I bet there's about 10 or 20 people have eaten spicy food. You know, I don't see any posts on this form about heartburn. Man, that means not a single human gets heartburn.

I'm really not sure where you are seeing any mention of a "problem." If one simply ignores the TCS OFF light blinking, I'm not sure what the consequences are. I may see a check engine light or a TCS OFF light on later. There may be no indication that a system was malfunctioning (as was the experience on my CX-7) but when you hit a strip of wet road, perhaps the TCS thinks you're trying to turn right when you are actually trying to go straight. Or perhaps your car provides significantly uneven steering assist (as with my CX-7). This may not be desirable. I'm not sure what you would see a post on.

A procedure may be "required" but have few immediately obvious consequences if not performed.

If it is in fact required, and you are trying to argue against it, consider that the steering angle sensor is used as an input for the control of important safety systems on the car. Before I would make such an argument in a public forum that it was not required, I would want to be far more sure about it. The fact that the TCS OFF light is blinking after disconnecting the battery, this indicates to me that the system is waiting for you to perform this procedure. I would not want to trust thin arguments for not performing something that could be a matter of life and death. So, care to back up your argument that it isn't required? I'd like to see something more concrete than the "10 or 20" line.

Again, I would suggest going out to your car, and disconnecting the battery as you have proposed. Note the flashing TCS OFF light, and perform the procedure as the service manual indicates. I'm not sure why you are so reluctant after announcing to everyone that you would try this.

In the mean time, I've ordered a cheap device to preserve the contents of the car's memory while the battery is disconnected. I think this has the potential to sidestep the problem sufficiently. I hope to preserve the setting that the Mazda dealer entered when performing the recent alignment.

 

[troutymouth]

However, if calibration was done previously, after disconnecting battery, it might need to be recalibrated again
if such new settings/parameters are not store in ECU (don't know either way).
Just my two cents.

This may help:

"The BCM stores the steering angle reference point using battery power supply. Therefore, if the following operations are performed and the power supply to the BCM is interrupted, the stored steering angle reference point will be erased."

And another excerpt:

"If the steering angle sensor reference point setting is not completed, it could result in an unexpected accident due to the related systems being inoperative. Therefore, if the BCM connector or negative battery cable are disconnected, or the BCM power supply is interrupted, always perform the steering angle sensor reference point setting and verify that each system is operational."

The source is the 2011 CX-7 workshop manual (my previous car). I assume since the procedures are the same, the systems are similar enough that it would be required. The reset procedure that follows this intro above is identical to the one for the CX-9

 

[pugsx]

Amazing that no one else has posted about this issue. Why is that? Didn't you just pick up your cx9? Did the dealer brush you off when you told them your light was blinky blinky?

 

[table5511]

In a years time, I average about 3 estimates per day on vehicles involved in collisions. They may or may not involve steering/suspension. That is 15 per week, 60 per month. I have been doing this for about 6.5 years. I can think of twice that I have paid for a steering angle sensor calibration. I pay for front end alignments all the time.

Just another thought.

 

[troutymouth]

Amazing that no one else has posted about this issue. Why is that? Didn't you just pick up your cx9? Did the dealer brush you off when you told them your light was blinky blinky?

My light was never "blink blinky." I have not posted any statement that it was. Not sure where this is coming from.

The light stops blinking once you perform the initialization procedure or turn the ignition on and off. Again, what issue you are speaking of? I don't see a "problem." Again: A procedure may be "required" but have few immediately obvious consequences if not performed. I asked the initial question because i wanted to things right, not half-a**ed.

Can you please re-read the excerpt above from the service manual. I'm not sure but I think that's a bit of a more qualified authority than estimating how many people "post" in a forum as your source.

n a years time, I average about 3 estimates per day on vehicles involved in collisions. They may or may not involve steering/suspension. That is 15 per week, 60 per month. I have been doing this for about 6.5 years. I can think of twice that I have paid for a steering angle sensor calibration. I pay for front end alignments all the time.

I respect that. I'm assuming a good alignment shop would probably perform this procedure if it's called for. On Mazdas specifically, the data is stored in memory that is cleared easily. That's pretty unique. I doubt customers would immediately notice the issue if the problem wasn't performed.