[ischmitz]

I am working on a 3.2 Carrera Motronic and found that one integrated circuit (IC) is most likely bad. Its input is low impedance and straps the injector signal to a fixed value close to GND. As a result the injector output stage does not work. Once I disconnect the input pin (4) of the IC the injector signal produced by the CPU looks normal again. Nice 4.3 msec pulses during cranking like one would expect at R418/R419 The IC is used to drive the injector output darlington transistor T402 and the fly-back circuit Y403/T404. My guess is it must be some type of custom op-amp or similar. It has some resistor network and filter components attached to it.

The part number is 0127 and the date code is 8712. It is a DIP-14 housing with logos from Bosch and Siemens on it.





I understand Bosch while never making their own semiconductors used custom-designed chips made by companies such as InterDesign and had other chips custom-labeled by many suppliers. Is there any recourse to find out a replacement part? What do others do to fix a problem like this?

Thanks,
Ingo