No power but good battery

MINNIVZ

MEMBER
2000 MITSUBISHI GALANT
2.4L
4 CYL
2WD
AUTOMATIC
200,000 MILES

I replaced the battery myself a couple months ago and have checked it with meter since having these issues. The problems started all at once. Worked at lunchtime and by the nighttime it didn't have any power to fuse-box or dash.

No lights in the dash when key is inserted. Got lights briefly and then they went out and car doesn't turn over. No clicks or grinding or anything. I turn the key and have no reaction from the car. When I use a wire to jump the power from battery to fuse box I can turn on car headlights. However, I shot continuity on battery fuse on red cable (120A) and the one in the fuse box (60A) and both were good. I have some type of aftermarket fuse-link for red cable but it has worked for years.

1 Reply

CARADIODOC

MECHANIC
33,871 POSTS

Follow the smaller positive battery wire to the under-hood fuse box and look at that connection. That has been a very common cause of this symptom on all car brands.

Turn the head light switch on so current is trying to flow, then watch for sparking at that connection when you wiggle that wire. The best way to verify that connection is the cause is to use a test light and check for full battery voltage on the terminal on the end of that wire, then move the probe a fraction of an inch, to the stud that terminal is bolted to. You'll find you have full voltage on the terminal but not on the stud. Tightening the nut will solve the problem, but the better repair is to remove the the cable and clean it.

Also follow the smaller battery negative wire to where it bolts to the body sheet metal. Be sure that connection is tight and not rusty. That wire can also corrode away up under the insulation where you can't see it