722.500 overdrive diagnosis question
 

in my 1990 300 sl w/a 722.5 automatic the 5th gear is not working. could someone tell me if there is a way i can determine if it is in the electronic control issue for the overdrive unit or an internal issue that would reqiuire a rebuilt tramsmission

thanks

Computer controlled system..MB scanners should be able to generate code that would allow for correct diagnosis.

thanks doc, is there any home remedy for this patient?
 

anything i can do say w/a test light and a power supply the see if the internal solinoid is working? i can pull the pan @ home also if that helps

not that i dont like shops, but doing it myself is part of the fun....

Check for fault codes, if not you are diagnosing a problem with you eyes closed.

If you have 5th gear at full throttle check for a disconnected vacuum line between the intake manifold and ignition control unit KZL/AKR.

thanks, ill have the codes puilled (nt)
 

nt