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Home >> Buick >> 1996 >> Century Base, 4D Sedan, 2.2 4 >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System - Tests W/Codes - 2.2L >> Diagnostic Trouble Codes >> DTC P0121 - TP Sensor System Performance >> Diagnostic Aids
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Diagnostic Aids

An intermittent problem can be caused by misrouted harness, rubbed-through wire insulation or broken wire inside insulation. If other DTC(s) are set for components that share the same ground and/or 5-volt reference circuit, check for faulty connections or wiring. PCM 5-volt reference circuits are internally connected within PCM. Also, using FREEZE FRAME data may aid in determining conditions present when DTC was set.

Fig 1: DTC P0121 Schematic
G96E01921