Question about 1999 GMC Sonoma

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20amp fuse in black box keeps blowing

20amp fuse in the black box under the hood keeps blowing. It is labeled ECM B. Iam told it is tied to PCM and VCM. After it blows the truck dies and when you turn the key back to the on position there is no fuel pump sound and the check engine light does not come on. After I change it everything is fine. A few days later with no warning it blows again. iam told it "might" be a short in the fuel pump itself but don't want to change the pump and find out this has been a problem and all it is, is a short in a wire somewhere else. Any experience or help with this problem? Thanx in advance

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The fuse ecm b it tied to the fuel pump, PCM, and VCM.
Fuel pump could have an internal short
check it by the way...


Posted on Oct 28, 2008

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