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Diagnostic Aids

Monitor voltage at each terminal shown above while moving related harness connectors, including PCM harness. If failure is induced, voltage will change. This may assist in isolating an intermittent condition. Check for bent pins at PCM and PCM connector terminals. If code reoccurs with no apparent connector problem, replace PCM.

Fig 1: Code P1650 Schematic (3.8L) QDM No. 2
G94I38578
Fig 2: Code P1650 Flow Chart (3.8L - 1 Of 2) QDM No. 2
G94C35313
Fig 3: Code P1650 Flow Chart (3.8L - 2 Of 2) QDM No. 2
G94B35312
Fig 4: Code P1650 Flow Chart
GB0013290