Cadillac Repair: 93 cadillac sedan deville electrical, digital speedometer, inner fenders

Question
QUESTION: Electrical speedometer is on the fritz, as well as the electrical gas gauge. sometimes it says E, or 2 or 5.. just goes crazy. Speedometer sometimes works ok , but mostly goes goofy and then down to zero. Ground wire issue?

ANSWER: ANALOG or DIGITAL speedometer cluster ?.

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QUESTION: Not sure how to answer that.. but the entire dashboard is electric.  Not sure what analog means

ANSWER: Analog means does the speedometer have the old style needle to show engine speed or does the speed show in digits ?.

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QUESTION: Oh! It's digital, the entire dash is digital. However I unplugged my battery and and reset everything, and the speedometer seems to be working, but I dont know for how long. Other issues, that might be electrical and associated with the speedometer would be the digital gas guage is wrong sometimes, goes up and down, three of the four power locks dont work.

Answer
Check all your BLACK ground wires that are attached to the inner fenders especially near the battery. I would also attach a home made ground from the engine to the firewall. You can purchase a COPPER BRAIDED STRAP for this purpose at any auto parts store. Cadillac has alot of ground problems.