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Home >> GMC >> 1994 >> Forward Control 6.5 Y, Standard >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Tests W/Codes - 6.5L Diesel >> Diagnostic Trouble Code Charts >> DTC 19 - Crankshaft Position Reference Error >> Diagnostic Aids
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Diagnostic Aids

When PCM is in backup fuel, fast idle and poor performance problems will exist. Check for good connections at crankshaft position sensor and PCM.

Fig 1: DTC 19 Schematic ("G" Series) Crankshaft Position Reference Error
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Fig 2: DTC 19 Schematic ("P" Series) Crankshaft Position Reference Error
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Fig 3: DTC 19 Flow Chart ("G" & "P" Series) Crankshaft Position Reference Error
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