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Steering Column Tilt Motor Failure Lx470


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#1 RoderickGI

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Posted 11 October 2009 - 09:49 PM

G'Day folk,

I've had no luck searching for other people who have had a Steering Column Tilt Motor fail on a Lexus LX470 (mine is a 1998, 110,000 Km). Plenty of people have had failures of the tilt motor on other Lexus vehicles, but not the LX470. I seem to be the only one!

Anyway, mine failed some time ago, but the telescoping motor still works fine, and the steering column tilt was in a safe position to drive, so I have left it until now. I pulled the motor out during the weekend and found that I could not turn the motor by hand, even though it is a direct drive with no gearing at all. Suspicious and curious I pulled the motor apart and I can see why the motor is impossible to turn. A very strong concave disc spring pushes rotating and non-rotating parts together very firmly. In fact a disc with a ring on it like mylar contacts a set of fingers attached to the body. Frankly I can't see how this motor would ever have worked, but it did. It uses induction or something, and has no brushes. It must produced quite a bit of torque to overcome the friction designed into it! Actually I'm a bit suspicious that my Lexus dealer may have pulled the motor apart and put it back together wrong, but I can't really work out a better assembly sequence that wouldn't cause the friction between parts. The bearig is fine, and the whole motor is quite a highly engineered unit, with very accurate machining tolerances. It looks like the motor could be reconditioned, but I can't find any information on it let alone parts breakdowns or spare parts lists!

I had a quote of AU$470 from Lexus Australia sometime ago for a replacement motor. I have now found out that it is the same motor as used in the Landcruiser, so I should be able to buy the cheaper Toyota part, but haven't got a price yet.

The part number is Toyota 89231-60010, Denso 110750-0011 7T.

Anyone else has had such a failure, and if so, was the electric tilt motor is repairable? How much did it cost you, and when did you have it done?

PS: Yes, I could just put the motor back in with a better tilt position, but I like the automatic tilt and telescoping of the steering column, and I want it back!

EDIT: The Toyota part is AU$321.20. This is looking like the best option at the moment.

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#2 RoderickGI

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Posted 16 October 2009 - 02:36 AM

For future readers, I have replaced the tilt motor with a unit from Toyota. The updated part number was 89231-60022. There were only minor changes to the design.

The installation was not without challenges. First of all, mucking around with the old motor had resulted in the fault codes being set, so that the "Tilt and Telescopic ECU" would not try to run the motor. This meant that the new motor didn't run when I first plugged it in, which was a little disconcerting. However disconnecting the batteries for half an hour reset the ECU and fixed that problem.

I also found that the motor had to be screwed in to the threaded adjusting nut exactly the correct number of turns in order to have the steering wheel tilt the full range. The motor only does three revolutions and then stops, in either direction. By correctly fitting the motor it stops before the circlips on the threaded screw hit the threaded adjusting nut. Correct fitment means that the motor doesn't try to continue rotating after it has hit the hard stop of the circlips, which could result in triggering a fault code, or damaging the motor.

I couldn't remove the threaded adjusting nut from the steering column to clean it out, and since I wanted remove most of the old grease including in the adjusting nut, I screwed the old motor into the nut and cleaned away the grease it pushed out. Since I didn't care about the old motor, I screwed it in as far as it would go, and about half a turn more, which of course rotated the spindle in the motor. The spindle of both the old and new motors can't be turned by hand.

When I had unscrewed the old motor I plugged it in again and surprise surprise it worked. :o Not as well as the new one, but it did rotate three full turns in each direction, the same as the new one.

So, either the old motor always worked, but the fault codes were set so that the ECU didn't try to run it. I don't think this was the case though, because I had had the batteries disconnected for extended periods previously, and the tilt motor never started working. The other possibility is that by pulling it apart and reassembling, then rotating it half a turn, the motor was reset back into a functioning starting point. That is, previously it had been rotated out of its range of operation somehow, perhaps because of an overload cause by lack of lubrication, and rotating it back into its range of operation enable it to work again.

I did have Lexus look at the motor once because it was a bit noisy, so maybe they pulled it out, incorrectly reinstalled it, leading to an overload, or they just rotated the motor out of its operating range. They looked at it a second time when it stopped working, and declared that the motor had failed. Now I know better.

Anyway, I installed the new motor, since I had it, and the old one can be a spare, or get recycled some time. The lack of solutions offered in this thread would imply that this is a rare issue. Maybe other Lexus dealers know how to grease a thread, and correctly use the diagnosis tools available to them. The tilt motor seems to be pretty robust if understood and treated right.

#3 congo34zulu

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Posted 21 October 2009 - 10:20 PM

For future readers, I have replaced the tilt motor with a unit from Toyota. The updated part number was 89231-60022. There were only minor changes to the design.

The installation was not without challenges. First of all, mucking around with the old motor had resulted in the fault codes being set, so that the "Tilt and Telescopic ECU" would not try to run the motor. This meant that the new motor didn't run when I first plugged it in, which was a little disconcerting. However disconnecting the batteries for half an hour reset the ECU and fixed that problem.

I also found that the motor had to be screwed in to the threaded adjusting nut exactly the correct number of turns in order to have the steering wheel tilt the full range. The motor only does three revolutions and then stops, in either direction. By correctly fitting the motor it stops before the circlips on the threaded screw hit the threaded adjusting nut. Correct fitment means that the motor doesn't try to continue rotating after it has hit the hard stop of the circlips, which could result in triggering a fault code, or damaging the motor.

I couldn't remove the threaded adjusting nut from the steering column to clean it out, and since I wanted remove most of the old grease including in the adjusting nut, I screwed the old motor into the nut and cleaned away the grease it pushed out. Since I didn't care about the old motor, I screwed it in as far as it would go, and about half a turn more, which of course rotated the spindle in the motor. The spindle of both the old and new motors can't be turned by hand.

When I had unscrewed the old motor I plugged it in again and surprise surprise it worked. :o Not as well as the new one, but it did rotate three full turns in each direction, the same as the new one.

So, either the old motor always worked, but the fault codes were set so that the ECU didn't try to run it. I don't think this was the case though, because I had had the batteries disconnected for extended periods previously, and the tilt motor never started working. The other possibility is that by pulling it apart and reassembling, then rotating it half a turn, the motor was reset back into a functioning starting point. That is, previously it had been rotated out of its range of operation somehow, perhaps because of an overload cause by lack of lubrication, and rotating it back into its range of operation enable it to work again.

I did have Lexus look at the motor once because it was a bit noisy, so maybe they pulled it out, incorrectly reinstalled it, leading to an overload, or they just rotated the motor out of its operating range. They looked at it a second time when it stopped working, and declared that the motor had failed. Now I know better.

Anyway, I installed the new motor, since I had it, and the old one can be a spare, or get recycled some time. The lack of solutions offered in this thread would imply that this is a rare issue. Maybe other Lexus dealers know how to grease a thread, and correctly use the diagnosis tools available to them. The tilt motor seems to be pretty robust if understood and treated right.


God damn bro, that is some seriously technical know-how. Are you a mechanic ? Also good looking out for future people who have this issue !

#4 RoderickGI

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Posted 22 October 2009 - 11:56 PM

Thanks for the kudos.

My father was a mechanic, and I'm a Mechanical Engineer, although I have mostly worked in the software industry.

But really, I'm just detail oriented and I like to fix things right, the first time.


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