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Voltmeter Is Inaccurate ("S" Series)

  1. Check for short, open, or high resistance between alternator Brown wire and cluster. Measure voltage between battery terminals. Now measure voltage between Pink/Black wire (terminal "A15") and a known good ground.
  2. If readings are different, repair Pink/Black wire. If readings are the same, check Black ground wire at terminals "A9" and "B7" for high resistance to ground. If Black wire is okay, replace inoperative instrument cluster.
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