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DTC P1635 - PCM 5-VOLT REFERENCE LOW Chevrolet Tahoe I

Note. For circuit reference (Схема №8)and (Схема №14). For connector and terminal identification, see CONNECTOR IDENTIFICATION.

Circuit Description

PCM provides a 5-volt supply for use in powering up sensors. This test monitors voltage present at PCM 5-volt reference terminals of boost and crankshaft position sensors, and optical/fuel temperature sensor (cam/hi res).

DTC will set when the following conditions are present

  1. 5-volt reference is less than one volt.