If as you can see in the Ford Focus schematic the second switch on the brake must be interrupted when you don't brake then I have the wrong switch. Thanks to this thread I am only aware of this switch (brake pedal sensor). My son and I have tested it thoroughly. It conducts electricity when you don't touch the brake.
The background is that the 4/4 has again this interruption since I changed the airfilter recently.
While other measures to repair the stuttering gas were always of limited duration, today we disconnected the switch. The car drives very constantly without the slightest interruption of the gas pedal. I will repeat both constellations over the next few days. Then I will have experiences which are no longer determined by coincidence and which lead to the assumption that the reason for the error has been found and that the error can be caused intentionally.
And there is something else as well. The car drives much better, as if it had always had to fight against the intervention of the current-conducting brake pedal switch since I had it. It sounds fuller, it accelerates more vehemently and the gas pedal is more sensitive. This means that everyone who has a 4/4 that doesn't stutter but has (perhaps also) the wrong switch will benefit.
In North Rhine-Westphalia we are allowed to drive a car without giving reasons. I don't have to overdo it but for testing purposes in not nice weather and in boring surrounding I use it.
I will report whether this measure is permanent. I have a very good feeling. Without wanting to say anything negative, it is possible that a whole series of 4/4 got the wrong switches, if we assume that the Ford focus schematic is correct. Intuitively I would say that the schematic is correct because you would have an open circuit under normal driving and you would send an impulse for what purpose ever (stopping fuel, deactivating a speed control etc.). If the good results are confirmed I will buy a switch that works the other way round. It is also obvious that an unattractive interruption is exactly what the switch is supposed to do...if it does it at the right moment for the right purpose and not at the wrong moment.
A note of caution, please ever disconnect any wiring which leads to the ECU before making a measurement of this switch.Not only to get the right impedance values but in first line not to damage the ECU because any impedance meter is using active current.
For those who are curious if the car drives better when the switch is out of function (or to see if it is the right or as in my case the wrong one), you must not demount anything because on the left side the cable can be pulled off easily with your fingers.If your switch is correct nothing will change, if not you may have a more pleasant drive experience. Please insulate the end of the teared off cable plug.
Last edited by Heinz; 14/04/20 01:19 AM.
