Ted_J

Help needed! I have a 2006 ML350 that is stuck in park. Pretty sure it’s the ISM, but I cannot get it to mechanic to have confirmed and repaired. Need to remove ISM and manually switch to neutral to tow on flatbed or trailer. Does anyone have directions or instructions to share on how I can get it in neutral?

Maj. Dundee

Does the engine start? Check fuse #111 in Eng. Compartment Fuse/Relay Box.

If the eng. starts, turn off eng., step on the brake & turn the key to position #2. Then try to move gear shift into NEUTRAL.

Ted_J

MajDundee,

engine will start if I reset the codes from the transmission, however, the codes come back and the red warning on dash returns as soon as I try to take out of park.

ill check this fuse just in case.

thanks,

Maj. Dundee

But you didn't comment on this............If the eng. starts, turn off eng., step on the brake & turn the key to position #2. Then try to move gear shift into NEUTRAL.

Maj. Dundee

What RED warning light?

And what are the code numbers?

Ted_J

Fuse 111 is good.

Red warning is “drive to workshop without changing gears”

ISM codes are 1904, 1922, and 1974.

Ted_J

also tried what you suggested, will not shift into neutral.

Maj. Dundee

Replacing the ISM is not an easy task as you would need a lift to do so.

The Auxiliary Battery allows the driver to position the shifter to NEUTRAL when there is a problem such as yours.

Access the Aux. Battery and test the voltage with a DVOM. Anything under 10 volts you must replace the Aux. Battery.

So if the Aux. Battery is faulty, replacing it is the only way you can have it towed to a dealer.

Ted_J

Aux battery checks good … tried process again, no Luck moving into neutral.

so back to my original question, is there a way to select neutral by accessing the selector on the side of the transmission?

Maj. Dundee

The answer to your question is no, not that I know of.

LILBENZ230

You cannot shift the car from park with a defective ISM. There is no manual override. To do so requires STAR - in the menu there is an option to move it to neutral and this is the only way. The ISM is a theft-relevant part, so you'll likely need the dealership or someone with the appropriate credentials to be able to repair this. Or I believe if you have access to a lift and the right knowledge/tools you might can ship it off to have it repaired and then it wouldn't need SCN coding like a new one.

Ted_J

Thanks for the reply LILBENZ230, i found a place in CA that says they can repair most, unfortunately one of the codes mine threw is not reparable. I have found an indy that says he can ensure diagnosis is correct, then replace ISM for me. My struggle has been finding the right tow company to get it there and not do more damage dragging it onto a rollback. That was the reason for my post in the first place. Had a friend send me info on another tow co today, so I’ll be checking with them this week. Thanks again!