is the overhead console in a 1999 ram2500 linked to the gas gage and if so if the gage is not working will the mileage show oc on it.

 

Linked is kind of a strange term here....... the PCM monitors the gas gauge..... and the overhead gets its cues from the central timer module. (basically, you have a small network in your truck, with the CTM being the hub.) If the truck doesn't know how much gas you have, I don't think it will be able to tell you much about fuel economy/range etc.

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