Question about 1998 Oldsmobile Bravada

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I cant find the negative side for the tach coil on the pcm module

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If you're talking about the coil itself, there is not a pos and negative because it's basically a transformer, with a primary and secondary side. If you're wanting to use a meter to read voltage, you would hold pos lead on either side and hold black or negative lead to engine ground. If primary is good you should read same voltage on each of the 2 wires.

Posted on Jul 13, 2009


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