Used Steering rack assembly programming

The only programming needed is, when the wheels are more-or-less straight and no one is putting any force on the wheel, whatever signal is coming from the new torque sensor at that point should be recognized as zero torque, so the steering computer has a function to say "look, remember this is zero."

The dealer can do that easily with their scan tool. If you have a Windows computer, a J2534 dongle ($400 ?), and a $55 subscription to techinfo.toyota.com, you can also do it easily with Toyota's software. Most other non-Toyota scantools will not give you access to steering functions.

There is also a way you can do it without a scan tool, just by carefully using wire jumpers at the TC (pin 13), TS (pin 14), and CG (pin 4) terminals of the OBDII port above your left knee. The exact sequence of steps you have to follow is in the manual - if you don't have that, you can view it on techinfo (even at the most basic, $15 subscription).

Here is a post that describes a handy sort of box that can be built with switches on the TC, TS, and AB lines that will allow you to do many of the things on the car that have alternative procedures for without a Toyota scantool.

For what you're doing, it might be less trouble to go pay the dealer for the few minutes it will take them to zero the steering with the scantool, than to learn how to do it yourself.

That's assuming the used rack you bought isn't already bad. One thing you could easily do is unplug the torque sensor connector at the ECU end (behind your glove box, the right connector has 4 skinny wires, white, black, red, and green) and measure the resistances between pairs of those terminals. Since I just had a new rack put in under warranty, we have the resistance readings for a good rack to compare to.

Good luck!
-Chap

 

I'm sorry to hear that, what a lousy experience.

In your original post, you didn't say much to describe what sort of trouble you had with the old rack. If the problem involved the wheel sometimes shaking by itself when you were not holding it tightly, that is the issue that Toyota's warranty enhancement covers (until December 2013). Because that's a common failure mode for these racks, it's probably a safe bet that a lot of them showing up used may already have it.

If you were having some different problem, or if Toyota says no on warranty coverage because of this repair attempt, you might still have options. The remanufacturer A1 Cardone does seem to list a reman version of this rack. They don't sell directly to the public but in the traditional channels to auto job shops (i.e., not the Pep Boys or AutoZones, but the grimy brick buildings in your industrial district with the old signs saying Larry's Auto or whatever; the ones your mechanics go to). The price isn't centrally set, you'd just call your local shop and ask. (The Cardone site does have a 'where to buy' tab that lists some online distributors, if you have trouble finding a local shop).

But since you've already had this lousy experience, would you be willing to describe exactly what problems you had with the used rack you bought, and how you finally determined it was bad? That might help out somebody later who is thinking of buying a used rack. Did the dealer tell you it was bad when you went in to have zero set? Did you make any resistance measurements on the rack? Do you still have it, could you take some measurements before you get rid of it?

Maybe out of your bad experience we can collect some good questions that other buyers could ask used-rack sellers before laying out the cash.

Thanks,
-Chap

 

Symptoms would help.

Bob Wilson

 

Did you try to turn the wheel with the power off? The reason I ask is I wonder if the 'tight' might be a mechanical problem versus the steering ECU trying to drive the motor.

I get the impression the original rack has a mechanical problem. If the car is not moving, does the power assist still turn the wheels?

Bob Wilson

 

The problem with the original rack sounds like a mechanical problem to me.

 

Ok, so it sounds like

1. The original rack suffered mechanical damage of some kind, not a torque sensor failure, so it wouldn't have been covered by the warranty enhancement anyway; no missed opportunity there.
2. The purchased, used rack turned out to have the classic torque sensor failure (which is probably why it was up for sale)
3. At the moment, the original rack seems to be working surprisingly well for a rack with mechanical damage. Turning the wheels with the car stationary, with the power assist working, is about the maximum mechanical force the rack needs to handle. I am surprised to hear that it does that successfully at all. When you do that now, can you still "hear and feel that something is wrong"?

When the dealer first told you the old rack needed to be replaced, did they say anything specific about the damage to it, or what code the ECU was giving at that time?

Driving on a rack that you even suspect is mechanically damaged worries me. I did drive mine with the torque sensor glitch for four years before having it replaced, but that only caused annoying glitches with the power assist, never any question about the mechanical soundness of the steering. Not knowing whether it could mechanically fail on you while driving is much more worrisome.

People with the known torque sensor problem are used to talking about just replacing the whole rack assembly, because the sensor isn't sold as a part. But some of the rack's mechanical parts (the inner tie rods and their attachment hardware, anyway) are available separately. Teardown and repair of the rack at that level is covered in the shop manual. With the boots off and the tie rods out, a person might see exactly what the damage was and what to do about it.

The trouble with that is, as you now know, just getting the rack out of the car where you can look at it and back in again is a $250 PITA. If your life allows you to be without the car for a little while, it might be worth taking your rack out to carefully examine it, where the possible outcomes might be:

• You find out it's really ok, and the bad sound/feel are from some other damaged suspension/linkage component, so you put the rack back in and fix the other thing instead.
• You find the damage and it's repairable, but you might have to order internal part(s) and wait for delivery.
• You find the damage and it's not to a part you can buy separately, so you have to order a new rack (or A1 Cardone remanufactured one) and wait for delivery.

If your life doesn't leave you the time to see what you find and then wait for parts orders, it might make sense to just order the reman rack up front. Spend the $250 in labor to take your old one out and put the reman in so you can drive your car. Then if you're curious enough (or if you're willing to look because we're curious enough) you could disassemble the old one to see what really happened to it. Maybe it becomes an easily repairable spare.

Or, when you find a shop that sells the reman rack, ask whether you can return it if it hasn't been installed. If so, you can buy it, have it on hand while taking your old one out, and then you can decide on the fly whether to just install the reman and be done with it, or return it and fix the old one.

In any case, if it were my car, I would definitely want to pursue the problem to a clear outcome. Driving around not knowing whether the steering will mechanically fail is not an attractive option.

Good luck!
-Chap