OK I disconnected the battery but the codes are still there. Clearing of the cache isn't done by disconnecting the battery. I was suspicious already as I had my accumulator taken out and recharged some 2 months ago. Car was without battery overnight. That would have cleared the codes. I disconnected the cable from the idle control on a running engine some 2 years ago. That must have been one of the codes I am reading now. I doubt this has happened any time since the last battery recharge.

Besides, using an original code reader one only needs to select a function to reset the cache. No accumulator disconnecting takes place. There must be some other way to do this. Any ideas? I know one has to either short some of the pins or apply voltage to some pins or a combination thereof. Only if I knew which pins.

I don't take the codes seriously yet. One of the codes says my engine temp sensor is faulty. However I am certain the system can only tell (and store in memory) when the switch has either been shorted or disconnected. It doesn't tell whether the readings are accurate.