My Wife's 98 Expedition has been having problems lately, rear whipper/front whippers/power locks/ power windows working when they feel like it. The blower motor would also stay on. The other night there was clicking from under the dash board from what sounded like to the right of the fuse box. The next morning awd 4wd low washer and another light in that cluster kept just going on and off randomly. I read up on the boards today and it seems like this behavior would point towards a water damaged GEM. I just spent the last hour and a half pulling the GEM and it looks fine to me. No corrosion, contacts all clean. I opened the case containing what I believe to be the GEM and it was clean as a whistle as well. I did go through the fuses and found 2 blown ones but I was receiving the above symptoms before they just stopped working today. So my question is can the GEM be damaged and show no signs? Or is my problem elsewhere?

 

That sounds like a voltage problem or a return problem(poor ground). Have you pulled out the DVOM yet?

 

This should answer your question, DVOM?

 

If you don't know the aconym DVOM you probably don't have one in the garage. Digital Volt Ohm Meter or can use that old analog Simpson you inherited from grandpa.

 

I had a poor ground between battery and firewall that caused all sorts of weird electrical problems. My fix was a new $1 battery terminal.

 

I know I have a volt meter, not sure if it's digital or not. I used it for when I was trouble shooting some switches on a bike I was building. I'm not an expert when it comes to electrical.... Definitely my weak point. I will assume that what you said wasn't rude because it seemed it.

Buzzard: I will check out the terminal cables and follow them to the firewall and see if I notice and problems.

 

The "Voltage Drop" method of troubleshooting should be helpful for you. As you move from point to point along and electrical conductor there should NOT be a voltage drop unless you encounter a load(device using electricity such as a lamp or motor or electronic module). If there is a voltage drop that's a problem. It's a sign of poor connections caused by corrosion or loose or damaged terminal or connectors. You have to locate them and repair them. Poor grounds have the same effect. They have to be clean and tight too or they can cause a voltage drop. These electronic modules need 5Vdc not 4.7. That's why a digital meter is important. A analog meter can't read with that kind of accuracy.

 

Thank you, that helps a lot more.

 

I had the same prob w my GEM - it looked fine (couldnt see any corrosiion etc) but it was NOT.... I know its a lot of dough to replace it - but your problems seem to be exactly like mine..... They wont solve themselves either. You should re seal your window too, thats where mine was leaking... GOOD LUCK this prob sucks!

 

Funny thing happened on Saturday...... a 98 Expedition eddie baurer 5.4 followed me home. I saw it while working and couldn't resist it for the price. So now this gives me more time to trouble shoot the XLT as I can take it apart and leave it apart instead of putting it back together for the next morning.