2016 Smart Fortwo Pure, silver and black, tinkering new mods now.
The past four months or so I've had a random SES warning light come on and put my 2016 For Two ICE in limp mode. Most of the time I can pull over, shut it off, and restart the engine and drive normally again although it takes four start cycles to clear the SES light as long as it doesn't still detect an issue. The SES light is always followed with the gauge cluster screen displaying a warning message stating "cruise control inoperative" if I was using CC at the time. Other times when not using CC and the SES light came on I would attempt to turn on CC (as a test) and then the same warning message would be displayed on the gauge cluster. This would happen randomly and sometimes two to three weeks apart on a daily driver. Last week it happened twice on a six mile trip to work and happened once the day before. So it is progressively happening more often it seems and having to suddenly drive in limp mode is dangerous at best. I've also noticed that the SES light and limp mode were instantly triggered one day when sharply hitting a hard bump in the road. This made me think about checking all wiring harness connections. I also recalled a post on here somewhere about a person having electrical issues and a shop finding where a radiator hose was rubbing and wearing down a spot on a large cluster of wires on a main engine wiring harness. I searched my engine bay and eventually wound up on the ground by the left rear tire. This is a picture taken from the left rear wheel well. There are only two wires that actually have exposed copper but it is evident that they were shorting from time to time. The radiator hose/heater hose easily flexes down and contacts the wiring harness by hand and under engine torque it may actually rest on it but I'm not sure. Either way this is a definite problem for me and could easily be a hard to diagnose issue for other 453 ICE owners. Yesterday I cleaned it out with electrical contact cleaner, dabbed some liquid electrical tape on it, and used zip ties to pull the wiring further away from the radiator hose just for a quick fix to finish the day. Today I will remove the rear tire so I can access it better and do some wiring repairs. I can only assume that this will fix my intermittent issue.....hopefully. I wanted to post this in case this is a wide spread and somewhat unknown issue.