What should the battery voltage be in 2006 cadillac sts

Nicole, I google it and the 06 Cadillac STS does appear to have a ignition relay. It will most likely be found in the engine compartment fuse/relay box. Check the attached links,instruction and guides, Good luck
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http://www.rockauto.com/en/catalog/cadillac,2006,sts,4.6l+v8,1432044,electrical-switch+&+relay,ignition+relay,3480
2006 Cadillac STS ignition relay Google Search

The fuse is located under the rear seat in the fuse box.Trunk/valet fuse.

Not the battery--- move on to testing the starting system

Im havung trouble finding the fuse box to change out my fuse for the cigarette liter

Most of the time, newer cars are going to be faster than older cars, unless they have been completely restored.-----------------------------------------------------------------------
FGTech Galletto 2

On this website you find information (diagram, description and location) about fuse boxes in Cadillac STS mk1 (First Generation; 2005 - 2006)

Cadillac STS mk1 First Generation 2005 2006 fuse box diagram Auto Genius

Go to autozone or o'reilly on line parts store and they have step by step instructions.

Check the fob battery you might need to replace it, The battery only has about a 3 year life

either your battery is flat or you have a starter problem or the terminals on the battery are not making good contact with the leads

one under the hood one on the drivers side of the dash