Reading 4Matic Codes
 

90 300TE 4Matic. The 4Matic light is always on. I'd like to read the codes from the computer to determine why it failed. Can anyone tell me where to read them and how they are defined?

Good morning Barn.as you can see from my id line i too have a 90 4matic.the light being on all the time means a fault code has shut down the 4matic CPU.try rebooting the cpu first.remove battery power for a few minutes.then start the car and count the blips of the 4matic light.one of the more common probable causes for a shutdown would be loss of hydraulic pressure due to leakage or low fluid level.:)

Thanks for the reply. I assume the codes won't be lost when I reboot the 4Matic CPU? Do you know which fuse powers the 4Matic CPU? How about a good source for a manual? Thanks

not sure which fuse.i usually disco the negative battery terminal.cant recall if codes will be stored after reboot but if anything is wrong they will comeback of course.ive been trying to get my hands on the official 4matic manual with no luck.but i do have some info on various 4matic issues that i can email:)