I installed a new double din radio in my 2005 F250 & backup camera . Now my speedometer doesn't work
You must have accidentally disconnected it.
I never touched the back of the instrument cluster or unplugged any of the wires on the instrument cluster .
All I know is it cannot be a coincidence.
Exactly! Check the fuses first. Also, some cars have the dash connected with the 'entertainment system', like some saturns for example, but I do not think it's the case here... Did you leave out any connectors that didn't fit the new unit?
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