The signal from my Engine Coolant Temperature sensor, (ECT), isn't making it all the way to my car's computer. I've tested the circuits and the ground wire for the ECT is fine, and is contacting the ground as expected, but the 2nd wire, the one that actually connects to the computer, (at Pin 2), isn't completing the circuit.

The wire is fine from the sensor to the top of the left-side wheel well in the engine compartment where I opened it up to test. Shortly after that it joins the left side tower harness, which both has a connection to the main engine harness and disappears through the firewall. I *think* the ECU wire goes through the firewall, but I'm not 100% sure. From there the wire must travel through the dash to the other side of the car where the computer is. I removed the panel above the pedals, (it's a Left-hand drive car), and can feel the tower harness coming into the vehicle, and there are a bunch of big connectors up there & other wires, but I haven't been able to find out what's going on.

So, does anyone have access to the plans for, or experience with, an 87 760 Turbo, and know where this wire goes, and where I might find a disconnected connection? FYI this is the grey wire that's in the middle of the concentric wire that leads from the sensor. It's still grey when it gets to the computer, so I'm guessing it's grey the whole way down.


(For background, this is the more specific "continuation" of my original thread: http://www.brickboard.com/RWD/volvo/1494885/740/760/780/electrical_puzzle_760_turbo_b230ft_wiringharness.html ).