P0700 Code help on a 99ML430
 

I just got the engine light on........and carefully drove it home.
The DTC code showing on a low end scanner is P0700. I don't feel any change in driving, but have heard a slight whine for about 3 weeks ( thought it may have been the PS, but now thinking otherwise)

I see many things it could be on the posts.
Any thoughts on what to look for 1st.....before bringing it in to the dealer.
It has 130k on it....just spent close to 4k for a steering rack after being stranded with some leaks.

Thanks in advance........Mike

My advice: Replace the transmission fluid right away? I bought my '99 ML320 at 132K miles with broken transmission. My Star manual says:This code is comming from transmission controle module:
a. Gear implausible or transmission with leaks
b. Command valve sticks in pressure position
Or have your dealer do diagnostics and code scan.
Please check the latest post with "lifetime" transmission fluid fill
Good luck!

You need to access the mfr specific codes in the transmission SDS scanner. From there, you can diagnose. It is not uncommon for fault codes for the output speed sensor "n3" in which case, they will likely replace the conductor plate which is the electrical portion of the valve body. Early model ml's had much more wear/tear due to the load of the vehicle but still pretty tough trannys though. Too expensive to guess on anything, especially with fluid at about $15-25/qt x 7-8. Sorry, any trans repair is going to be pricey. An independent which has an SDS scanner can also perform repairs.