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Speed Indicator Jumps Up And Down Erratically

  1. Remove speed sensor from transmission. Check that all gear are in good condition. Ensure retaining clip is installed and gear does not slip on shaft. If okay, go to next step. If not, replace drive gear and retaining clip.
  2. Disconnect wiring to speed sensor. Using ohmmeter, check resistance between 2 wires in harness going to speed sensor. Reading should be greater than 500 ohms. If reading is correct, go to next step. If not, repair wiring, cruise control, or instrument cluster for short circuits.
  3. Using ohmmeter, check speed sensor resistance. Reading should be 200-230 ohms. If reading is correct, go to next step. If not, replace speed sensor. Recheck speedometer operation.
  4. Connect speed sensor wiring. Remove instrument cluster. Using ohmmeter, check for intermittent resistance between pin "11C" and pin "7C" (ground). See Instrument Cluster Pin Connector Identification. If okay, replace speedometer module. If not, repair connectors or wiring from cluster to speed sensor. After repairs, check speedometer operation.
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