SL/R129: 1990 300SL not shifting into overdrive 5th gear
Junior Member
Joined: Apr 2018
Posts: 63
Likes: 3
From: Calgary
none currently
So if the overload switch is new - the cable checks out fine.. the car runs fine - the switch in the console functions and the transmission will go into 5th if I remove the HGS module - where should I look next...
Junior Member
Joined: Apr 2018
Posts: 63
Likes: 3
From: Calgary
none currently
Hello again - getting close to spring and driving season in Canada so I thought I'd take a another crack at this - At some point the previous owner replaced the OEM EZL unit with a rebuilt from RMT - I'm looking to source an OEM unit to see if that's my issue - but I do not know the correct OEM part number to look for - does anyone have a 1990 SL300. that they can look to see the MB part number on the EZL in the car. The RMT website lists several dozen part numbers as cross reference. I tried a couple of website to look up by vin number without any luck. THE RMT EZL has M104-R010-ADFU - which according to them is correct for the car but I don't know if its functioning to send a signal to the transmission solenoid - if you read the first part of the story the transmission shifts into fifth if I pull the transmission module N51 - so my guess is the module is not getting a proper signal from the EZL...
any advice from a MB guru would be appreciated -
any advice from a MB guru would be appreciated -
Banned
Joined: Dec 2019
Posts: 75
Likes: 12
From: Hemet, CA
2003 SL500, 1991 500SL
I'm just reading the last post in this long thread. The EZL provides a load signal to the transmission control unit. If you have an issue with that signal I'd expect a diagnostic code "3". Also, the signal from the EZL is easily tested. For more help go to Benz Global dot org.
