v70 temp/fan problems. multiple engine temp sensors?

[richardgengle]

i have an odd problem with engine temperature and radiator fan on a 2004 v70. it makes me think that there are 2 engine temp sensors? is that true?

you see -- the radiator fan never comes on, unless i reverse the positive and negative leads. the red and black wires yield 14v accross them. the purple signal wire is always 0. even so, the temperature gauge acts properly and reads cold on start, and after 10 minutes of the engine running, reads halfway between hot and cold. NORMAL.

however, the gauge reads same whether the ECT[under the thermostat] is connected, disconnected, or shorted. MOREOVER if i short the ECT, the engine runs bad on start, and the fan still wont turn on and the signal wire still reads 0.

so its getting some readings, but it all makes no sense, unless the ECT is not what controls the guage or fan... just what controls how the ecm controls the engine..

Does anyone know if there are multiple temp sensors