The electrical side of it has circuits that run from the power-train control module to the optical fuel temperature sensor. If there is air the the fuel system the light will come on. Make sure fuel system is free of air. I would suspect that the optical sensor is faulty. I do not believe that it is service separately from the fuel injection pump.
Here is a schematic of the circuits:
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Here is a picture of the pump assembly. Optical fuel temp sensor is #1.
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Hope this helps.
Cly
Wednesday, July 25th, 2007 AT 5:09 AM