Aloha all,

My 05 Roadster did the 'won't start but everything works' today.
The key fob would not unlock the doors, thought the fob batteries died.
When I got in and tried starting the car it did not turn over but all dash lights lit up fine.
Then the alarm went off and I could not stop it. The fob did nothing. Inserting the key did not shut off the alarm. Locking the door with the key did not stop the alarm.
Alarm would stop on its own after a minute. Then the side marker lights would blink for several minutes. (seemed this was a way of saying the car was immobilized) I could hear a clicking or sound like a blinker behind the dash/vents. Sorta like the wipers on intermittent mode...
I tried rolling the car back a little, swapping the fob batteries, and nothing worked and the alarm would go off again.
Open the hood and the alarm would go off. What an embarrassing situation. Everyone in the parking lot was eyeballing this.
Not much I could do as the few tools I had were stuck in the locked trunk.
So a call to roadside assistance and a tow to the shop was needed.
A check of the car battery and it was fine, both in and out of the vehicle. Starter was AOK.
After a while the guys at the shop figured out if you pull fuse # 9, a red 10 amp fuse, that isolates the door locks SKREEM etc. I could then start the car.
No interior lights, door, console, or trunk locks though. Oh and Sprint Booster was disabled too.
But while the car is running I had them put the fuse back in, of course the SKREEM sets off the alarm but I could unlock the trunk and center console and car stayed running. Whew.
So in an hour they figured out that fuse 9 was a "bypass" or work around to that SKREEM module.

So I am driving it with no worries. I will order a used Ebay SKREEM module (door lock control) and see if it works. If not able to program key or something I will send one to SOS for repair/programming.

Hope someone else with a SKREEM no start problem tries pulling fuse 9 and can post their outcome.

Cheers!!



Of note.
You'll need to remove fuse #9 after you unlock everything, or alarm will go off as you drive, or while car is running.

Also if you take the battery cable off 30 times it will fry the ECU.
This is a safety feature MB designed into the cars. It appears to the car that you are trying to steal it and drive it without proper key, etc.
So DO NOT REMOVE AND REPLACE THE BATTERY TERMINAL REPEATEDLY OR YOU WILL FRY THE ECU.
A couple times is fine, just don't get carried away!!
On another site my tech showed me the conversation he had with a MB tech about the SKREEM and the battery cable removal.
They pointed to a Mercedes forum where a dealer did remove the cable after alarm would go off while diagnosing and chasing the problem.
The car owner had the dealer put in writing that they had pulled it 30 times, 21 more times, it was their fault if the ECU fried.
The dealership did sign the paper and yet continued to pull the cable off.... The dealership ended up buying the car owner a brand new ECU when they fried it.
What is funny is my tech had to run out to the bay and stop the mechanics from repeatedly pulling off the battery cable. Guess they didn't want to buy me a ECU
So if your ECU was fine, then it is fried (check codes if possible with OBD scan tool before towing or dropping off at dealership) I would ask them to replace the ECU at their cost since they did not know what they were doing.

Good luck with the fuse #9 temp fix and don't pull that batt cable more than necessary til you get SKREEM replaced or problem diagnosed properly.

Aloha!