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After a trip to the dealership for an alignment (new tires), the techs said my front ride height sensor was dodgy (I have been getting the occasional "shock absorber" indicator light) and needed replacing.

They cited 6.5 hours to swap out the part which I thought was kind of high for one of the few parts that can actually be seen on the car and looks relatively easy to replace. I'm sure the sensor needs to be calibrated after installation via the suspension computer, but surely it couldn't take that long.

I was thinking of getting the part myself and doing the swap, then take it to an independent shop for the calibration.

Anybody know the part number for the front ride height sensor (that links to the front sway bar) for a '97 SL600?

Thanks.
 

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The part # is on the lid to the sensor. Same PN for front and rear. That's a $450 part! How much does that light bother you? ;)

I'm interested in what they are taking 6.5 hours for? swapping the part is 15 min of work so there must be a heck of a lot of calibration going on. Here in the bay labor + part would be about $1500 per your quote. :eek:
 

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$450 for just the sensor is a few bucks.

The light doesn't even come on in the cooler months and usually only when I have the Sport/Comfort rocker on Sport, so it's not like it comes on all the time. After three starts, the light goes out.

Wonder if it just needs reseating or something, better not be loose. I need to investigate this further. No part number offered other than me yanking out my existing sensor and taking a peek?
 

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Sorry I don't have a PN handy, I'd just find it the way I suggested for you. You don't have to pull the sensor to see the PN. Just look under the car (will be easier to see the rear, it's RIGHT THERE by the pass rear tire).

That sensor is basically just a potentiometer. Has a 5V and Gnd connection on pins 1 and 5 (going off memory), the other two pins are the output of the pot. When the lever is at the notch in the lid it is 5V, Opposite side 0V, aligned with the connector is about 2.5. As it spins around 180 degrees it goes from .2 to 4.8V and then decreases back to .2 through the next 180 degrees. What is my point? Anything they are calibrating would be easily calibrated yourself with the adjustable bar that attaches to the car body. Either there is something else they are doing or they are crooks. I'm interested like I said to see what the 6.5 hours or labor are getting you.

If the issue is temp dependant a). you probably have five months of no issues and b). you could throw a heat gun on there and see if you get the light.
 

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I removed the sensor over the weekend to see if there was anything obviously wrong with it and record the part number.

The part had full rotation of the sensor arm and appeared to be in great physical shape. Even the plug connection looked good. By the way, it's a 6 pin connector with pins for 1, 4, 5 and 6. I didn't bench test the unit as this was just an exploratory mission and the day was ending.

I did lower the ride height though.

The original linkage setup only left about an inch of adjustment and my ride height was about 2.5 inches too high (looks like a stock SL500 tire gap) after I had a dealership alignment at the first of the year. I shortened the linkage by almost the remaining 1 inch and lowered the car for a test. I turned on the engine and let the car adjust and boy did it lower, about a quarter inch tire gap. So, it isn't a 1 for 1 lowering ratio. I readjusted the linkage for about a half inch from the original setting and got the ride height where I wanted it.

The sensor's Part Number is 010 542 74 17 and it's made by helag.
 

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Discussion Starter #6
Update.

I did swap out the sensor, but it wasn't the problem (misdiagnosed repair by the dealer mechanic again). I don't know what the problem is yet, but I've found a new independent repair shop and I might give them a crack at it.

The warning light is just a notice of ride height and comes and goes with every 3rd start of the engine, so it's just an annoyance.

As for adjusting the ride height on an ADS car, it couldn't be easier.

When the ride height sensor gets changed out, you have to separate the height linkage to the body. I would recommend marking that linkage to make it easier to reassemble for both a frame of reference and an index. The linkage halves are serrated and the serrations are a very fine (1/32", or so). This gives a clue as to how sensitive the sensor really is. Less linkage lowers the car while more linkage raises the car. I would say the ratio is one serration to about a half inch of body movement, so make small adjustments and leave at least an inch and a half of fender clearance if you have the 18" sport rims or you are going to have some fender damage. You can go closer with the regular 16" rims as they aren't as wide and won't interfere with the fender lip. After making a change you have to start the car and let it settle to it's new height. Use the raise body rocker by the lights to go up and down to check your work. I wouldn't just drive off after making a change or you might have tire/fender issues.

The ride height sensor ONLY adjusts the ride height as the car sits, so if the front left of the car is a 1/4" higher than the front right, too bad. The whole front of the car goes up or down together. Same with the back. There is no individual corner adjustment. For that you would have to manipulate the springs with spacers or cutting.
 

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Right sits lower by quarter inch

Hi , were you able to solve the problem?
My car sits quarter inch lower on the right side than the left. My car is a RHD.

I have the same issue of ADS light coming on & off.

Car raises on both the settings quiet well. only on the standard setting it is a little difficult to drive on bumps & pot holes.

How can this only one side low issue be solved.

I am in no mood to throw parts at the car with parts prices sky rocketing in my part of the world.

Thanks in advance
 

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Update.

Use the raise body rocker by the lights to go up and down to check your work. I wouldn't just drive off after making a change or you might have tire/fender issues.

The ride height sensor ONLY adjusts the ride height as the car sits, so if the front left of the car is a 1/4" higher than the front right, too bad. The whole front of the car goes up or down together. Same with the back. There is no individual corner adjustment. For that you would have to manipulate the springs with spacers or cutting.
My 99 SL600 is low on the right front. In trying to fix it I found too many serration's go a long way and you are right about just driving off. I made a hard left turn standing on the gas at a stop light with my 18" 245 tires and took the lip out of my right front fender:frown
 

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Discussion Starter #9
I originally started this topic before I gained much more knowledge about ADS. I guess this is part of the process.

Anyhow.

ADS can only deal with front and back ride height (they are in fact 2 somewhat separate systems) not side to side. If you have a side to side ride height issue, this is dealt with in the traditional way by using the various MB spring cushions (indexed by the visible notches). Or you may have a collapsed/tired spring. ADS springs are somewhat incidental to ride height as they don't actually support the weight of the vehicle, the hydraulic fluid filled front strut and rear "shock" absorbers do. The springs mostly just are along for the ride and probably only provide harmonic damping. With no fluid in the system, the car will settle almost down to the jack lifting pucks (no kidding).

Figure out which front side you want to normalize and get either a thicker or thinner spring cushion to even out the resting bias. When both sides are equal, adjust the ride height linkage between the ride height sensor and the sway bar to get your desired ride height for the front of the car. One benefit of ADS soft springs is they are MUCH easier to R/R than regular springs. Easy Peasey.

The original problem that this thread refers to (ride height sensor) wasn't the problem (as diagnosed by MB), but the yaw and pitch body sensors. There are three on the car, one on each strut tower and one in the trunk just ahead of the vacuum pump. The two strut tower sensors had mostly expired due to years of under-hood heat and posted errors to ADS when they warmed up during driving.
 

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I originally started this topic before I gained much more knowledge about ADS. I guess this is part of the process.

The original problem that this thread refers to (ride height sensor) wasn't the problem (as diagnosed by MB), but the yaw and pitch body sensors. There are three on the car, one on each strut tower and one in the trunk just ahead of the vacuum pump. The two strut tower sensors had mostly expired due to years of under-hood heat and posted errors to ADS when they warmed up during driving.
Do those front sensors cause the ADS to react to body roll? My car only has 60K on it but it is 19 yrs old. I cant say there is a lot of difference in cornering with the sport selection. This is the only ADS car I have ever driven so no way to compare. I have changed the pump thinking maybe it was weak and of coarse changed fluid and filter. I even toyed with making a smaller pulley for the pump to gain more pressure at lower RPM's It does raise and lower as it should. I never have had a code on it.
 

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Spring cushion, what does it mean?
Will this be available with MB to an open market vendor?

I am guessing the entire strut will have to be removed to add this spring cushion , right?

Thanks in advance

The springs mostly just are along for the ride and probably only provide harm
Figure out which front side you want to normalize and get either a thicker or thinner spring cushion to even out the resting bias. When both sides are equal, adjust the ride height linkage between the ride height sensor and the sway bar to get your desired ride height for the front of the car. One benefit of ADS soft springs is they are MUCH easier to R/R than regular springs. Easy Peasey.
 

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Discussion Starter #12
Nope.

The A-arm gets separated from the ball joint while the A-arm is lowered until the spring is free. The cushion is at the top of the spring. You would reassemble in the reverse order using a thicker cushion.

There are more concerns (safety related) to this procedure, but it's essentially as simple as this.
 
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