Did some tracing with an ohmmeter. The single wire from the pressure switch goes to one of the terminals of the overboost protection solenoid connector. If the other terminal of the connector gets switched +12V, then it makes sense that the pressure switch should be normally closed, which then makes a working circuit. But I did not find switched +12V on the other terminal of the overboost protection solenoid, and the pressure switch is open, a double fault. How likely is that? I can really use a wiring diagram. Can someone buzz out their pressure sensor and the overboost protection solenoid connector? Which fuse is this circuit on?

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85 300D turbo pristine w 157k when purchased 167,870 July 2025
83 300 D turbo 297K runs great. SOLD!
83 240D 4 spd manual- parted out then junked