Mechanics

WHAT DOES THIS DIODE DO?

1993 Ford Ranger

Electrical problem
1993 Ford Ranger 6 cyl Two Wheel Drive Manual

A diode in the fuse box under the hood has gone bad. When I replace the diode with a small jumper wire, the truck starts and runs fine. Otherwise, it will act like its going to start but doesn't, as if it is not getting gas. But when I turn the key, I can hear the fuel pump run.

This part is labeled only 'diode' and has no explanation in the lid of this fuse box or on the part itself. What does this part do? Would leaving the jumper wire in place fry something else? I am having trouble finding this part.
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Jkdasa
October 25, 2009.



Welcome to the forum, the diode shows to be in the voltage leg that goes to the coil side of pcm power relay. The diode allows voltage to flow in only one direction, toward the relay. Preventing voltage/current spike in the opposite direction toward the pcm. Radioshack may have a diode that will work?

JDL
Oct 25, 2009.