Date: Sat, 24 Nov 2001 19:05:55 GMT From: "Neal L. Grotenstein" <nealgnopsamg.org> Subject: 1985 900S, 8 valve. Want schematic
Hi Stick shift car Back-up light works, brake light does not. I bought a Haynes Manual, #84010 THe schematic of Figure 13.51 shows +12 feeding the (normally open)brake light switch, then on to the brake lights. THe other side of the brake lights are grounded. THat sounds logical. Back to the car: This will sound weird.. Everything was measured with a voltmeter and an ohmeter. I'm an electrical engineer. Lots of analog design before s/w converted us all. The brake switch on the brake pedal is normally closed. THat switch also has a vacuum line. Can't tell where it goes. There is an identical switch on the clutch pedal both SAAB p/n 951-2294. I can't see where the vacuun hose from it goes either. Of course, the switch contacts are also normally closed. Thus both switches show no resistance when their pedals are not pushed in, and no current flow when when they are pushed. THey are wired in SERIES, so that one is wired to the next. As in brake switch clutch switch ------x___x---------------x___x---------- - ----> 2 pin to 2 --> --------------------------------------------> plug pin socket --> With the plug in the socket and the engne running, the 2 pin socket is shorted out, and 0 volts & 0 amps( <1 ma) are read. With everything off, and the plug removed from the socket, there are 1,530 ohms across the 2 socket pins. I realize this sounds weird THat is what is there. Comments? Neal Grotenstein nealgnopsamg.org www.cpcug.org/user/nealg/
