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HOMESERVICE MANUALSGMC1999FORWARD CONTROL 5.7 R, AUTOMATICREPAIR AND DIAGNOSISEXTERNAL PAGESDIFFERENT CARSECTION 239 (ENGINE CONTROLS SELF-DIAGNOSTICS - 3.1L ENGINE)DIAGNOSTIC TESTSDTC P1635: 5-VOLT REFERENCE 1 CIRCUIT (MALIBU)CIRCUIT DESCRIPTION
1999 GMC Forward Control 5.7 R, Automatic

Circuit Description

1999 GMC Forward Control 5.7 R, AutomaticSECTION Circuit Description
WARNING: This page is about a different car, the 2003 Pontiac Grand Prix, 2003 Chevrolet Malibu, and 2003 Buick Century. However, it is still accessible from the selected car via links, so may be relevant.

The Powertrain Control Module (PCM) provides 5 volts to the following sensors:

  • The Manifold Absolute Pressure (MAP) sensor.
  • The Exhaust Gas Recirculation (EGR) valve.
  • The Throttle Position (TP) sensor.
  • The Exhaust Gas Recirculation (EGR) valve position sensor (Grand Prix only)

These 5-volt reference circuits are independent of each other outside the PCM, but are bussed together inside the PCM. Therefore a circuit condition on one sensor 5-volt reference circuit may affect the other sensor 5-volt reference circuits. The PCM monitors the voltage on the 5-volt reference circuit. If the PCM detects the voltage is out of tolerance, DTC P1635 sets.

RENDER: 1.0x

NO RELATED

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