Speedometer says 70 at idle.
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2003 Chevrolet Silverado 3500 Question: Speedometer, volts, temp gauges don't work properly.
Answer #1G. T. Service Center (4231 Answers) , Stephenville, TX - (254) 638-3236ProfessorG December 11, 2013, 07:03Master
The 03 instrument cluster had problems, send it in to be rebuilt or purchase another, the only fix.
Answer #2All-Car Specialist, Inc. (6 Answers) , San Gabriel, CA - (626) 768-9074allcar December 11, 2013, 09:20Enthusiast
we send our clusters out to AER in La Habra Ca. to be repaired. did you try the gage function reset in the Tech 2 scanner
Answer #3Mr. Whizard October 02, 2014, 05:43Technician
Common problem with these 2003 and some 2004 instrument clusters. They can be repaired - it is not a fault of any other part of the vehicle. For repair of these clusters go here: http://www.mrwhizard.com