1997 Mercury Marquis no power

Have you tried a jump-start to see if something drained the battery? Have you measured the battery voltage? It will be 12.6 volts if it's fully-charged. If that's what you find, follow the smaller positive battery wire to the under-hood fuse box. Check that connection to be sure it's clean and tight.

It is clean & tight, wont take a jump either. Im trying to find out if there is a fuse or relay that controls power

Exactly which model and engine size do you have? All I can find is a Grand Marquis with a 4.6L but that's a rear-wheel-drive. You need to supply accurate information so I can look up the right wiring diagram.

It is 4.6 rear wheel drive. Sorry just a woman trying to figure out the problem

The problem is the insane engineers have seen fit to hang a computer onto ever possible system, so it's hard to determine what should still be working. Is there anything that works now? in particular, it appears the power door locks should work. See if you can find anything with a hint of life. If you can't, you'll need a test light, then we'll start at the battery and try to find where we're losing voltage.

I am having the same problem as above. I'm going to check the positive cable for integrity and get back with you.

Hi,

I noticed it has been a few days since we heard from you. Has any progress been made? We are interested in knowing.

Let me know.

Take care,

Joe

When we wiggled the positive battery cable, we got power intermittently and at one point was able to start the car. We're going to change the terminal on the positive cable, and we think that will do the trick. There's a lot of corrosion where the wire meets the terminal, but the whole thing is pretty old, original parts.

Absolutely, that sounds like the problem. Make sure to clean the negative as well and make sure both are clean and tight.

If you have a chance, let me know how things turn out for you.

Take care,

Joe