300se w126 1989 mercedes benz automatic does not change gears or it goes on nutral whilist driving?

ASR can be dangerous, I highly recommend a dealer or highly recommended mechanic look at. Could be complicated, or just some loose connections affecting both asr and Transmission.

Did you get the system re gassed and new air con oil? If not that's prob the fault

For gear shift issues and gear stuck issues,the help links are provided below. Click the link below to go through troubleshooting procedure:---- ---- Car will not move when in gear?

http://repairhelpcenter.blogspot.in/2012/02/car-will-not-move-when-in-gear.html ---- transmission sticks in first gear? http://technoanswers.blogspot.com/2012/01/mercedes-benz-transmission-sticks-in.html ----- Transmission not engaging in first gear? http://technoanswers.blogspot.com/2012/01/mercedes-benz-not-engaging-in-first.html ----- Vehicle only goes in First gear?

http://howtobyme.blogspot.com/2011/11/chrysler-pt-cruiser-only-goes-in-first.html

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Car is stuck in park and the shift will not move?

http://howtobyme.blogspot.com/2011/08/car-is-stuck-in-park-and-shift-will-not.html

---- Engine will not go out of park mode? http://technoanswers.blogspot.in/2012/02/2002-nissan-sentra-will-not-go-out-of.html ---- Car stuck in park? http://technoanswers.blogspot.in/2012/02/nissan-sentra-stuck-in-park.html ----- Car will not come out of Park?

http://howtobyme.blogspot.com/2011/11/car-will-not-come-out-of-park.html

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Automatic transmission will not go into high gear?

http://howtobyme.blogspot.com/2011/11/automatic-transmission-will-not-go-into.html
--- Car wont downshift sometimes?

http://schematicsdiagram.blogspot.com/2011/12/car-wont-downshift-sometimes.html
---- Transmission will shift into drive?

http://schematicsdiagram.blogspot.com/2011/12/buick-park-avenuetransmission-will.html
----- Auto wont shift from park? http://schematicsdiagram.blogspot.com/2011/12/ford-taurus-wont-shift-from-park.html ---- Car Transmission will not go into Park mode?

http://schematicsdiagram.blogspot.com/2011/12/car-transmission-will-no-go-into-park.html
----- Shift indicator directly goes to 2nd when key is turned ON?

http://schematicsdiagram.blogspot.com/2011/12/shift-indicator-directly-goes-to-2nd.html
---- Third gear missing and engine losing power?

http://schematicsdiagram.blogspot.com/2012/01/third-gear-missing-and-engine-losing.html
------- Vehicle has whining sound in gear?

http://technoanswers.blogspot.com/2012/01/chevrolet-silverado-has-whining-sound.html
----- Hard to shift gears on Manual transmission?

http://technoanswers.blogspot.com/2012/01/hard-to-shift-gears-on-manual.html
------ Car hard shift at slow speeds?

http://technoanswers.blogspot.com/2012/01/car-hard-shift-at-slow-speeds.html
--- Automatic transmission shift lever hard to move on cold mornings?

http://technoanswers.blogspot.com/2012/01/automatic-transmission-shift-lever-hard.html
------ Gear shifts hard?

http://schematicsdiagram.blogspot.in/2012/02/2000-nissan-maxima-shifts-hard.html
------- Vehicle noticed sluggish delayed shifts while driving?

http://schematicsdiagram.blogspot.in/2012/03/vehicle-noticed-sluggish-delayed-shifts.html

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This will help.

Thanks.

Can be purchased on line from Mercedes benz

http://www.bing.com/images/search?q=1993+Mercedes+Benz+belt+diagram&qpvt=1993+Mercedes+Benz+belt+diagram&FORM=IGRE


Follow this link to the belt diagram.

Change fluid, check modulator? Very old MB towing any number of things could have happened to that transmission. Could be a vacuum leak.

If the buttons stick yes. Call a junkyard and get a replacement.

Aux heat pump maybe failing. Its on the passenger side by the battery. Follow the hoses. Its moves water to the heater core.

I know it's a little large, but here's the belt routing diagram you are looking for. Hope it helps!

Hello, I have worked on Mercedes for the past 20+ years and I can't think of any way to do this easily. The shift lock is tied into your steering lock/ignition lock for safety and theft reasons.
I hope this helps.
CYA, Gator241