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Test SD, Speed Indication Jumps Erratically

  1. Checking Driven Gear & Retainer Clip: Remove speed sensor from transmission. Ensure driven gear is in good condition, and driven gear retainer clip is installed. If components are defective, replace as necessary. If components are in good condition, proceed to step 2).
  2. Checking Speed Sensor Wiring: Disconnect wiring connector at speed sensor on transmission. Using ohmmeter, measure resistance between wires of wiring harness to speed sensor.
  3. Resistance should be greater than 500 ohms. If resistance is okay, proceed to step 4). If resistance is less than 500 ohms, check speed sensor wiring circuit between instrument cluster and speed sensor.
  4. Checking Speed Sensor Resistance: Using ohmmeter, check resistance between speed sensor terminals. Resistance should be 200-230 ohms. If resistance is within specifications, proceed to step 5). If resistance is not within specifications, replace speed sensor.
  5. Checking Wiring To Instrument Cluster: Reconnect speed sensor wiring connector. Disconnect negative battery cable. Remove instrument cluster. See INSTRUMENT CLUSTER R & I  .
  6. Using ohmmeter, check for resistance between instrument cluster connector C2-2, pin No. 31 (Gray/Black or Yellow/Light Blue wire) and connector C2-1, pin No. 4 (Pink/Orange or Black/Light Blue wire). Resistance should be 160-230 ohms.
  7. If resistance is within specifications, replace instrument cluster. Install door pillar sticker to indicate instrument cluster has been replaced. If resistance is not within specifications, check connections and wiring circuit from instrument cluster to speed sensor. Repair wiring as necessary.
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