Ignition switch questions
my girlfriend's 2006 E350 is having key/ignition switch issues.
the key won't even turn most of the time, though I got it to turn once or twice since it "broke".
I charged the battery (to rule out low battery) for a while and key doesn't work even while being jumped.
The dash is not lit most of the times, although sometimes I see the mileage when inserting the key.
1) Is this a key gone bad, or the ignition switch?
2) I've seen on ebay some salvage yards selling matched key/Ignition Switch/Engine control module/column lock. in the 350-500 range with 2 keys
will that work? how much of a pain is it to replaced the matched column lock? can you just forgo the column lock and buy JUST the key/Ignition Switch/ECM ?
Thanks
I've seen some youtube videos that suggest it's prone to failing in the next gen models.
how difficult is it to reach/swap the lock module (I'm leaning to buying a matching set of keys/switch/ecm/colum lock)
Thanks and Bump
- Lock the doors with window down using key
- Reach in and unlock doors manually
- Put key in ignition and leave it there for at least an hour or so
If this fails you may need new key, internal circuit board may have failed. Only definitive way to know what is happening is to have someone check for fault codes using MB DAS (diagnostics).
Last edited by konigstiger; Sep 11, 2017 at 01:26 PM.




I'm wondering if it is just the Infra-red transmitter diode in the fob end that codes the ignition module or is it also triggered by the RF chip inside.
When you point the end of the key fob directly at the little black plastic window on the driver's door handle and press the "unlock" button the car unlocks right? If you hold it longer the windows should go down also. This would at least tell you the infra-red portion of the key fob is transmitting and give you a way of rolling down the windows if the ignition module is having issues.
Do the same procedure with the "lock" button on the fob to get the windows to go back up. If you have a sun roof it will actuate also.
Last edited by Sleeper Benz; Sep 11, 2017 at 01:28 PM.
the fob buttons didn't unlock prior to the no start issue.
Today when I looked at the Fob circuit in well lit conditions, I noticed there is a chip (one that has just two end connections) was broken off one end.
When I press down on the chip, I am able to see the red led on unlock/lock etc. I am going to re-solder it and from there see if It works.
I am afraid the EIM went into security lockdown, but with working buttons I might be able to bring it out of that.
Last edited by gallanalero69; Sep 11, 2017 at 09:55 PM.
the coil on the key circuit had it's front most post loose as well. I carefully heated and reflowed the solder and they key was back to normal.
door locks still don't work, but the fob now lights up red when buttons are pressed. I told my girlfriend to run get a new key because this one is falling apart and will fail again.
Last edited by gallanalero69; Sep 12, 2017 at 02:53 AM.
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