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Discussion Starter #1
When I drive over 80 km/hr the triangle on the dash comes on. This means the 4matic is working. Do you have any idea what could be the problem? Could it be a speed sensor problem?
My Mb dealer dos not have a clue beacuaese he has no experience with the older 4matic systems.....

Best regard Robbert
 

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'92 300TE 4matic 280,000miles, '92 300TE 4Matic 'Ice Blue Metalic' 101,000miles
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When I drive over 80 km/hr the triangle on the dash comes on. This means the 4matic is working. Do you have any idea what could be the problem? Could it be a speed sensor problem?
My Mb dealer dos not have a clue beacuaese he has no experience with the older 4matic systems.....

Best regard Robbert
OK, you don't say the model, yr or the mileage?:confused: There were transfer case problems until they were worked out about '91. Start with the basics in the system-sensors. Make sure your 4matic fluid never got low and let any air in...another reason for the light to come on occasionally. It's a very complicated but wonderful system and if the 'basics' don't reveal anything, find someone who is an expert at 4matics....not someone to poke & pry.

Kevin
 

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'92 300TE 4matic 280,000miles, '92 300TE 4Matic 'Ice Blue Metalic' 101,000miles
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Sorry, it's a 1991 300 TE 4matic with 190000 km
History? Ever a problem before with the 4matic system/light? Did the fluid ever get low (way below its dipstick level)?? Anything ever replaced in the 4matic system? Any leaks in the system? You're right on the cusp ('91) for transfer case problems...although you should have had that by now.

Kevin
 

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Discussion Starter #5
The 4 matic light came on before. It seemd there was a problem with the 4matic valve control unit. I had this replaced. Now the 4 matic light is off, the front wheels kick in again, but as I mentioned the triangle on the dash now comes on over 80 km/hr.
So this problem started after my mb dealer replaced this unit. They looked at it but becuase they have little experience with the older 4matic systems they have no clue at all....

Robbert
 

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'92 300TE 4matic 280,000miles, '92 300TE 4Matic 'Ice Blue Metalic' 101,000miles
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The 4 matic light came on before. It seemd there was a problem with the 4matic valve control unit. I had this replaced. Now the 4 matic light is off, the front wheels kick in again, but as I mentioned the triangle on the dash now comes on over 80 km/hr.
So this problem started after my mb dealer replaced this unit. They looked at it but becuase they have little experience with the older 4matic systems they have no clue at all....

Robbert
Well, if you want to attempt this fix yourself, you need a flow chart for troubleshooting the system. Otherwise, you'll just be substituting parts for a 'fix'. It's a complex system and so you need some substantial documentation to proceed. Do a search here and see if you can turn up some 'fixes' for the light coming on at certain speeds. I'm wondering if they even bled the system properly after the valve control unit was installed. Seems like they were throwing parts at it, as well.

Kevin
 

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'92 300TE 4matic 280,000miles, '92 300TE 4Matic 'Ice Blue Metalic' 101,000miles
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Very few stay the course with 4matic issues. My guess is that they dump the cars and hence never resolve the problems that we eagerly await an answer for.

My suggestion is to pay the $20 (or whatever it is now) for the 24 hr shot at the WIS. Make sure there is LOTS of paper in your printer and give it your all to copying everything they have in there about 124 4matics. That should take some of the voodoo out of the system. Just don't expect the 4matic brain to be a great diagnostic tool. You're going to have to be more intuitive than that.....

Kevin
 

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w124 300 turbo diesel 4matic sedan
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Hi, Im pretty sure that the problem is the abs rings on your front driveshafts. They are full of rust and dirt, so that the abs sensor cant sens the rotation when the speed gets to "high". Result is, the system gets signal from the rear wheels spinning/they are going faster than the front wheels (sensor says that the front are not turning because of signal failure) If the problem had been constant, it could have been a abs sensor failure, but when it comes with speed increase, its a signal reading problem. When the signal says front wheels are turning slower than the rear wheels the 4matic system does what it should, power to the front wheels and if that is not enough, lock up the rear axle, and that is what your's is doing, the triangle is NOT 4matic indicator, its lockup indicator for the rear axle. Clean up the sensor rings at the front axle, and maybe grind the top of the sensor rings to get a more "readable" surface for the sensor.
 

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'92 300TE 4matic 280,000miles, '92 300TE 4Matic 'Ice Blue Metalic' 101,000miles
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Hi, Im pretty sure that the problem is the abs rings on your front driveshafts. They are full of rust and dirt, so that the abs sensor cant sens the rotation when the speed gets to "high". Result is, the system gets signal from the rear wheels spinning/they are going faster than the front wheels (sensor says that the front are not turning because of signal failure) If the problem had been constant, it could have been a abs sensor failure, but when it comes with speed increase, its a signal reading problem. When the signal says front wheels are turning slower than the rear wheels the 4matic system does what it should, power to the front wheels and if that is not enough, lock up the rear axle, and that is what your's is doing, the triangle is NOT 4matic indicator, its lockup indicator for the rear axle. Clean up the sensor rings at the front axle, and maybe grind the top of the sensor rings to get a more "readable" surface for the sensor.
That's rarely necessary unless you live in some extreme salt-belt. A good brake cleaner on the stator ring as you rotate the wheel, followed by a good polishing of the ABS sensor is all that's necessary. And I sure as hell wouldn't change the gap by grinding anything.

Kevin
 

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'92 300TE 4matic 280,000miles, '92 300TE 4Matic 'Ice Blue Metalic' 101,000miles
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It's a shame these wonderful cars are so fatally flawed. I have a 91TE that will hit the junk pile later this year.
Offering parts????? I need the 4matic 'brain' control unit as a substitute test unit.

Kevin
 

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That's rarely necessary unless you live in some extreme salt-belt. A good brake cleaner on the stator ring as you rotate the wheel, followed by a good polishing of the ABS sensor is all that's necessary. And I sure as hell wouldn't change the gap by grinding anything.

Kevin
-well, you do not grind the top if it is "flat" so the sensor can read every step, but if rust have eaten the metal so the top is sharp, then you cant get a good reading. I had the same problem as "boskerrji" who posted the first message. But mine had the problem at 60 km/h, and sometimes when parking, full lock up. I cleaned the rings, and the problem moved to 80/90 km/h. Then I grinded the top of the ring, very careful, and voila, I can do 160km/h and not one problem at any speed. This is 4 years ago, and still no problem, going strong every winter, I live in Norway, and we do have winter. But I could have done what the local dealers said, "just replace the TC and front drive shafts, cost: 100.000,- nok /20.000 dollar, and then you probably have solved it...." so I think it's worth a shot to try this, it costs you a cupple of hours. But if you DONT know how this works, and dont know how to grind the rings without messing up the sensors ability to read the signals, and maybe reduce the gap between the sensor and ring after grinding, well, just dont do it.
 

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'92 300TE 4matic 280,000miles, '92 300TE 4Matic 'Ice Blue Metalic' 101,000miles
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-well, you do not grind the top if it is "flat" so the sensor can read every step, but if rust have eaten the metal so the top is sharp, then you cant get a good reading. I had the same problem as "boskerrji" who posted the first message. But mine had the problem at 60 km/h, and sometimes when parking, full lock up. I cleaned the rings, and the problem moved to 80/90 km/h. Then I grinded the top of the ring, very careful, and voila, I can do 160km/h and not one problem at any speed. This is 4 years ago, and still no problem, going strong every winter, I live in Norway, and we do have winter. But I could have done what the local dealers said, "just replace the TC and front drive shafts, cost: 100.000,- nok /20.000 dollar, and then you probably have solved it...." so I think it's worth a shot to try this, it costs you a cupple of hours. But if you DONT know how this works, and dont know how to grind the rings without messing up the sensors ability to read the signals, and maybe reduce the gap between the sensor and ring after grinding, well, just dont do it.
Interesting solution, as I've never seen the stator teeth that rusted away. It makes sense though if they can get that disfigured.:thumbsup:

Kevin
 

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Wouldn't the stator problem also trigger an ABS warning light?
 

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'92 300TE 4matic 280,000miles, '92 300TE 4Matic 'Ice Blue Metalic' 101,000miles
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I dunno, I'm going by what flymo says and hopefully, he's correct. I think I'd replace the stators from a used model rather than grind them down. Obviously, there is some sort of acceptable range in the air gap between the sensor and the stator.

Kevin
 

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Wouldn't the stator problem also trigger an ABS warning light?
In my case it didn't, seems like the 4matic is more sensible than the abs, I dont have any other expl. This was the main reason it took me quite some time to figure it out too, it SHOULD be a abs warning light, but it wasn't. I even manipulated the abs signal to see if the abs lamp would light up, and it did, so I didn't spend more time with this tread for some time. Then, when I couldn't find any explanation to why this happend, I went back to "rotation sensors", it had to be something "telling" the 4matic system to engage frontaxle and lockup. If there is a crack in a ring, it shuld be a abs warning light, if there is a bad conection or like a wire broken inside the insulation, it shuld be a abs warning light, and the error shuld come at any time, slow speed/high speed, when you turn etc. But if the error is consequent at one speed, Im pretty sure it's problems with counting the tops of the rings. You dont have to "grind" more than giving the tops a little flat head, if they are sharp. Good luck, and the best part is: it cost you only some labour : )

-if anyone out there can help me with a hyraulic oil leak problem I would be happy. Hydraulic oil coming out of the breath valve on top of the TC!!!!???? anyone have a good idea???
 

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'92 300TE 4matic 280,000miles, '92 300TE 4Matic 'Ice Blue Metalic' 101,000miles
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In my case it didn't, seems like the 4matic is more sensible than the abs, I dont have any other expl. This was the main reason it took me quite some time to figure it out too, it SHOULD be a abs warning light, but it wasn't. I even manipulated the abs signal to see if the abs lamp would light up, and it did, so I didn't spend more time with this tread for some time. Then, when I couldn't find any explanation to why this happend, I went back to "rotation sensors", it had to be something "telling" the 4matic system to engage frontaxle and lockup. If there is a crack in a ring, it shuld be a abs warning light, if there is a bad conection or like a wire broken inside the insulation, it shuld be a abs warning light, and the error shuld come at any time, slow speed/high speed, when you turn etc. But if the error is consequent at one speed, Im pretty sure it's problems with counting the tops of the rings. You dont have to "grind" more than giving the tops a little flat head, if they are sharp. Good luck, and the best part is: it cost you only some labour : )

-if anyone out there can help me with a hyraulic oil leak problem I would be happy. Hydraulic oil coming out of the breath valve on top of the TC!!!!???? anyone have a good idea???
If you pull the fill plug from the side of your TC and you get a mix of hydraulic oil & ATF spilling out, your TC is toast. It will require a rebuild to replace the aluminum piston with a steel piston & seal, bench bleeding and/or a factory rebuilt TC. The TC is overfilling with hydraulic oil and mixing with the ATF. At least this is the problem from the way I'm reading your post.

The factory TC should be replaced on all these cars, sometimes as early as 50,000 US miles. Here from a dealer, they run between $3,000-$8,000USD, which of course exceeds the value of the car many times over.

Kevin
 

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Thanks for the bad news : ) I'll try this.
The car has 365 000 km on the meter, but is in good shape. Maybe I'll take a junkyard tour and see if I can find any. Is there a way of finding out who's rebuild and who's got the alu piston?

flymo
 

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'92 300TE 4matic 280,000miles, '92 300TE 4Matic 'Ice Blue Metalic' 101,000miles
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Thanks for the bad news : ) I'll try this.
The car has 365 000 km on the meter, but is in good shape. Maybe I'll take a junkyard tour and see if I can find any. Is there a way of finding out who's rebuild and who's got the alu piston?

flymo
Sorry...but it's an old story/symptom.:(

The factory rebuilt TC's will have a sticker that says as much on the TC itself. I would look for one of those. Try to stay near your production yr though, because there were some ring gear changes along the production timeline.

PWogaman here has pulled like seven of them from salvage yards. He has the procedure down to a science and what to look for in the yr changes.

Kevin
 
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