ECU issues
Thread Starter
Newbie
Joined: Jun 2023
Posts: 3
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2015 C350 Coupe Base
ECU issues
Just finished changing out plugs and coils on 2015 c350 coupe. Plugged ECU back in after finishing everything up and the engine is trying to roll over, even without the key FOB in the area. Only way to get it to stop turning over is to unplug the ECU. To make sure I didn't screw up the install, I unistalled the coils and plugs, then reinstalled them making sure the plugs are torqued down to 23 Nm. Checked the electrical connections and vacuum lines on manifold to make sure I didn't miss anything. Has anyone heard of this?
MBWorld Fanatic!
Joined: Jun 2012
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From: Toronto
2022 E53 AMG
Not sure why you need to remove the ECU and just not lift it up and push it to the side. Did you disconnect the power and ground the car before removing the ECU? If not, you could have caused a short in the ECU and caused it to fail. I would remove the power, ground the car, making sure the keys are 5 meters away before you do any of this.
Thread Starter
Newbie
Joined: Jun 2023
Posts: 3
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2015 C350 Coupe Base
Thanks for the reply. I did not remove the ECU. It is necessary to unplug the connection on the the front of the engine in order to lift it up and move it to the side. In hind sight, disconnecting the battery would have been beneficial, although speaking to a few local mechanics, disconnecting is not a common practice, but I am afraid that the ECU is fried. The key FOB was more than 5 meters away and at no time was the car under power during the repair. Anyway, it got towed to a local repair shop and is getting worked on because this is beyond my capabilities. Thanks again for spending the time to reply.
MBWorld God!
Joined: Dec 2019
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Thanks for the reply. I did not remove the ECU. It is necessary to unplug the connection on the the front of the engine in order to lift it up and move it to the side. In hind sight, disconnecting the battery would have been beneficial, although speaking to a few local mechanics, disconnecting is not a common practice, but I am afraid that the ECU is fried. The key FOB was more than 5 meters away and at no time was the car under power during the repair. Anyway, it got towed to a local repair shop and is getting worked on because this is beyond my capabilities. Thanks again for spending the time to reply.
