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HOMESERVICE MANUALSCHEVROLET1992CAVALIER RS, 2D CONVERTIBLE, 3.1 T, STANDARDREPAIR AND DIAGNOSISEXTERNAL PAGESDIFFERENT CARSECTION 4 (ENGINE CONTROLS - TESTS W/CODES - 3.3L PFI)PCM/BCM CODE CHARTSCODE 31, PARK/NEUTRAL SWITCH CKT
1992 Chevrolet Cavalier RS, 2D Convertible, 3.1 T, Standard

Code 31, Park/Neutral Switch CKT

1992 Chevrolet Cavalier RS, 2D Convertible, 3.1 T, StandardSECTION Code 31, Park/Neutral Switch CKT
WARNING: This page does not describe the selected car, but rather 6 other vehicles, including the 1992 Pontiac Grand Am, 1992 Oldsmobile Cutlass Cruiser, 1992 Oldsmobile Cutlass Ciera, 1992 Oldsmobile Achieva, and 1992 Buick Skylark. However, it is still accessible from the selected car via links, so may be relevant.

Park/neutral switch contacts are part of neutral start switch. Contacts close to ground in Park or Neutral and open in Drive. Code 31 will set if park/neutral signal circuit indicates an open for 3-4 consecutive starts or if conditions occur as follows:

  • Code 38 does not exist.
  • Circuit No. 434 indicates ground.
  • Transmission is in high gear.
  • TCC is locked (4T60 transaxle).
  • TPS is less than 15 percent (.94 volt) and vehicle speed is greater than 45 MPH (3T40 transaxle).
  • All above conditions have been met for at least 12 seconds.
NOTE: Test numbers refer to numbers on diagnostic chart.
  1. This tests for a closed switch to ground in Park.
  2. This tests for an ungrounded Park/Neutral input in Drive. Be sure TECH 1 display reads DRIVE, even when wiggling shifter. If it doesn't, check for intermittent contact at neutral safety switch.
  3. This tests for a faulty ECM.
Fig 1: Code 31, Schematic, Park/Neutral Switch Ckt, "A" Body
G91C07413
RENDER: 1.0x

NO RELATED

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