Hi all, 
I've been troubleshooting my C280 for the past 2 months after having gotten it back from the mechanics. Whilst with them they found an issue with the instrument panel where it would intermittently not work at all whatsoever (no gauges moving, only backlight behind clock) and then it would come on randomly, then off again after restarting the car.
As well as this, after having it back from them, the throttle began to have issues as well. When pressing the accelerator, the throttle would go up and seemingly not be read for half a second, then be read again and so on so forth. Here is a video which shows how it behaves: (3:00 minutes in), though not same model, still same behavior. I've also followed the procedure in that video but to no avail.
I ran HFMScan on it and the log it gave me was as follows: (file attached too)
6/21/2019 4:34:23 PM
__________________________________________________ ___________
022, Post
CC/EA signals emergency running mode.
Unmetered air, throttle valve jamming.
Cruise control or electronic throttle to emergency running.
__________________________________________________ ___________
104, Post
Safety fuel cut-off from electronic accelerator or CC activated.
!!! Only with EC or CC !!!
except USA J, 202, 210 USA.
Verify fuel cut-off control from EA actuator, CC actuator.
IGNITION=ON -> voltage jumps : 2,2-11V.
So far I have replaced the ECU with another exact same one and swapped the throttle body for another one.
Does anyone know how to approach this problem? Has anyone experienced any of these two issues before and managed to fix them? I've been troubleshooting this car since mid last year and really wish to get it fixed
Any advice or suggestions greatly appreciated!
I've been troubleshooting my C280 for the past 2 months after having gotten it back from the mechanics. Whilst with them they found an issue with the instrument panel where it would intermittently not work at all whatsoever (no gauges moving, only backlight behind clock) and then it would come on randomly, then off again after restarting the car.
As well as this, after having it back from them, the throttle began to have issues as well. When pressing the accelerator, the throttle would go up and seemingly not be read for half a second, then be read again and so on so forth. Here is a video which shows how it behaves: (3:00 minutes in), though not same model, still same behavior. I've also followed the procedure in that video but to no avail.
I ran HFMScan on it and the log it gave me was as follows: (file attached too)
6/21/2019 4:34:23 PM
__________________________________________________ ___________
022, Post
CC/EA signals emergency running mode.
Unmetered air, throttle valve jamming.
Cruise control or electronic throttle to emergency running.
__________________________________________________ ___________
104, Post
Safety fuel cut-off from electronic accelerator or CC activated.
!!! Only with EC or CC !!!
except USA J, 202, 210 USA.
Verify fuel cut-off control from EA actuator, CC actuator.
IGNITION=ON -> voltage jumps : 2,2-11V.
So far I have replaced the ECU with another exact same one and swapped the throttle body for another one.
Does anyone know how to approach this problem? Has anyone experienced any of these two issues before and managed to fix them? I've been troubleshooting this car since mid last year and really wish to get it fixed
Any advice or suggestions greatly appreciated!
Junior Member
Check your engine wiring harness. Up through 1996, engines with the HFM fuel injection, like yours, used a biodegradable engine wiring harness that falls apart after time and engine heat. That last date of manufacture on the bad harnesses, not the car itself, is supposedly 11/95. There's a good video explaining it here:
Cheers for that, I think today I will check my entire wiring harness for any faults. I've seen the wires inside of the harness and they seem to be the non-biodegradable kind, but nevertheless there could still be faults.
