Hi,

First off, thank you all for this awesome forum!


I have a 99 ml320 with 260K Miles on it. and this is the FIRST major problem it's given me.

I drove it yesterday for a good 200 mile and parked it at night, then when i went to drive it in the morning, i noticed that it was revving much faster and went through all five gear by the time it was going 20MPH!!!!!!!!!!!

Then i noticed that the low range light was on, so i pulled over, put it in neutral and hit the low range button to no avail, just 3 blinks and it was still on.

I came back home and disconnected the battery for 20 mins and turned it on again, still stuck in low range, then i got underneath it and told my friend to hit the low range button and nothing (no vibration or sound from the transfer case motor) i tapped the motor a couple of times with a hammer too, but nothing.

so i have come to the conclusion that either my transfer case motor is bad, OR my transfer case controller module is bad (if these cars even have one).

both are pricey. I was wondering if you guy have any troubleshooting tips to pinpoint the problem. help me please, the car gets about 6 miles to the gallon because of this. not to mention that i have to change the oil since its been revving soo much.

I'm a mechanical engineer and love working on cars, so DIY is not an issue for me.





P.S i scanned the ECM and the only relevant code i got was a 137. something about CAN not being able to communicate with the TCC


ANY INFO IS APRECIATED!!!

Thanks,
RAY