dorfer21

2012 C300 4Matic Sport.

1) Bought the car with a known trans issue.
2) Replaced the trans with a rebuilt trans (722.964), during which I found out there are 2 different trans housings, deep oil line connection and non, but that's an aside.
3) buttoned everything back up, hooked up battery (new in February, has good voltage and tests out OK.)

Went to start the car, it cranked and but wouldn't start for 3 tries, then went silent. I can hear the ESL unlocking and the steering wheel moves freely. No errors on the scanner other than the one listed. EIS reports as unlocked.
Dash says to 'Take key out of ignition", like the key is no longer recognized. It does this with both keys, and I replaced the key fob batteries to verify they are good as well.

Checked the starter and associated fuses, they're all good.
Removed starter, bench tests good, same as the replacement I bought (subsequently returned)
Removed and replaced alternator. with a reman Bosch unit. Verified all fuses in the starter/alternator cable are still good.
Still no crank/no start condition.

I don't see any wires that are out of place or anything that is missing. This car does have a remote start system that I cannot identify as I don't see any modules anywhere and it uses the OEM key fob. It's a press lock 3 times to start thing, I'm not sure if that may have something to do with it.

I don't think this is an EIS/ESL issue given the reports from the scan tool. This is giving me fits!

Any advice from the hive mind?

EDIT: I think the remote starter module it has may be causing the issue. I'm going to pull the EIS and see if removing the remote start module is the culprit and report back.

Also, the YOUCANIC scanner is really good. I've used it on this C300, a 2011 GT500, a 2016 Durango and 2 2018 Ram 2500's (one diesel, one a 6.4 Hemi power wagon)

dorfer21

No joy on the remote starter.
The car is now at the dealership and they are running diagnostics, so far its an issue with the communication to the starter on channel 87.

TimC300

Was the car starting and running when you bought it, prior to replacing the transmission?

Wonder if they will recommend replacing the ECU?

Elemento Tuning

Did you transfer over your conductor plate from the old transmission to the new? Those are vin locked and if you used the new one it will not work.

CaliBenzDriver

Newly replaced 722.9 tranny job...

• then crank + no start
• then no crank + no start
• then msg "take you key out"

Ouch, how rude is that car!

The tranny needs to get remarried to your car security with a Xentry. I think Peter @BenzNinja can make this all right again without having to tow your car anywhere.