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Speed Indication Jumps Up & Down Erratically

  1. Remove speed sensor from transaxle. Check that all gear teeth are in good condition, retainer clip is installed and gear does not slip on shaft. If gear and clip are not okay, replace as necessary.
  2. If gear and clip are okay, disconnect speed sensor connector. Using DVOM, check resistance between 2 wires in harness to speed sensor. Resistance should be 500 ohms. If resistance is less than 500 ohms, repair wiring of circuit No. 150. Check cluster for intermittent short or open circuits and recheck speedometer operation.
  3. If resistance is greater than 500 ohms, use DVOM to check for intermittent resistance at speed sensor. Resistance should be 200-230 ohms. If resistance is not as specified, replace speed sensor and recheck speedometer operation. If resistance is 200-230 ohms, reconnect speed sensor wiring.
  4. Disconnect battery ground cable. Remove cluster. Using DVOM, check for intermittent resistance between pins No. 8 and No. 12 of cluster connector "A". Resistance should be 200-300 ohms. If resistance is constant, replace cluster and affix odometer sticker to door pillar. If resistance is intermittent, check connectors and/or wiring from cluster to speed sensor (circuit No. 150).
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