I have a 2000 5.4L expedition that is having an electrical problem I think. Started with a bad alternator, that was replaced, then after experiencing the dash lights flickering and hesitation when you get on it a little, we found the alternator had a bad diode, so replaced it again. Now, we are experiencing the hesitation and occasional flicker, but the alternator tests good, battery new, and no codes. Check it with code reader at Autozone. They suggested taking to dealer, but don't trust the local dealer. Could it be a computer of sorts that might have gotten fried from the bad alternator putting out AC? why don't I get some codes? almost runs like its not getting air or fuel when it starts acting up. Any help would be greatly appreciated!!!

 

This sounds like a bad ground issue... make sure all your grounds are clean and the wires are not green in color if they are buy some battery terminal cleaner from napa and spray on all the corrosion let is soak then hose it off with brake clean.... make Sure all the bolts that come in contact are tight and iff there is any rust buildup under the terminal remove and grind the rust off. Make sure the ECM is grounded good. .

 

Make sure your windshield is not leaking on the drivers side. My electrical problems were due to a messed up GEM Mod from water leaking in. It caused my wipers and windows to stop working but only sometimes. Itwould also try to engage my starter while already being started which led to a burnt out starter.

 

It wasn't the ground and it wasn't the windshield leaking. The hesitation has almost disappeared, and the flicker on the odometer light and radio light has become more sparatic. There are no codes to work with. Someone at Autozone suggested one of the computers was flaking out - he had run into that before - but could not remember which one. I really need to get this fixed so I can get rid of it. I've lost my patience with it and my wife has lost her confidence in her SUV. Please help!!

 

The GEM module controls all the body electrical ,the lights ,radio ,windows,running boards, abs,airbag, My truck is at dealer having dealer only GEM module replaced because of strange things going on only every once in a while. T he truck was like haunted. The GEM is a computer and is 500.00 dollars.

 

thanks for the input. My issue seems to be just in the radio lights and instrument panels lights for now. Can't afford to be bent over backwards at the repair shops, so will live with it for now. thanks