HELP , anybody have a wiring diagram for the 740 turbo wagons. I have no brake lights, there is a good fuse but no voltage at the brake switch. What is between those two points??? I first noticed this when the cruise control stopped working, looking into that is when I found this problem with the lights. All other electrical works, just the cruise and the brake lights.

PS: Also where is that anoying door open buzzer so I can disc. it...

THANKS
Matthew

Problem Solved!

There are TWO switches on the brake pedal for slush box cars(automatic). The lower is for the shift interlock and the upper one is for the brakes. The upper one is almost hidden and hard to get to.
I replaced the brake switch since it was just about shot and still no
lights. Next step is the bulb out relay and that fixed it. Strange because I checked the continity between the brake pins on the relay and it looked OK. Just goes to show that elctricity is a strange thing ....

My '93 940 diagram shows a connector between Fuse 4 and the brake light switch. It's an 8-pin connector (C7) "at the steering column" (good hunting).

GN/Y wire from Fuse 4 goes thru C7 pin 2 to the BL switch.
BN/Y wire comes from the BL switch, thru C7 pin 1 to Bulb Failure Sensor.
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Bruce Young
'93 940-NA (current) — 240s (one V8) — 140s — 122s — since '63.

Can't think of any way for this to be true. Possibly the wire has pulled out of the bottom of the fusebox but that's a long shot.

The brake switch is replaceable; if that is not the problem, the "bulb out" relay is downstream of it. That's the point where the single circuit splits to two for left and right lights. Red canister. They can be easily replaced or resoldered inside if you can find the point on the top circuit where it burns out.
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Rob Bareiss, New London CT ::: '87 244DL/M47- 234K, '82 245T/M46-182K, '84 242DL/AW70-100K, '89 244DL/AW70- 212K and I miss my: 86 244DL 215K, 87 244DL 239K, 88 744GLE 233K, 88 244GL 147K, 91 244 183K

The bulb out relay on my 87 740 caused the brake lights to quit working. It is the round red relay in the front left side of the relay tray.