pkek925

Okay so the car ran perfectly fine and everything was until until one rainy day I started up my car, drove 10 minutes away, parked, then started the car again but this time after about 5 secs the car shut down. I checked it to be the 80a Battery fuse under my hood and thought maybe some water dripped and caused it, So I replaced it and drove back home. Now the car did the same thing after 5 seconds of it starting up but now everytime I replace the fuse and go to hook up the negative batt terminal it blows. Dotn even know where to begin with this one other then cleaning my terminal heads.

Former User

Check the alternator wires. Otherwise, the hood fuse box may be bad.

pkek925

will do, got my voltmeter in hand to see if i can check. Ive looked and people said that it could be the starter wiire as well. Can the fuse box itself really go bad?

Former User

The starter motor is not protected by any fuse.

Fuse boxes have internal circuits that can short out.

pkek925

They were referring to the cable running to the starter motor from the battery touching the outer portion of the starter. does that fit for how my cars been acting? Becasue I got it to start for a couple seconds is the thing. Btw is there any way I can check the fuse box or specifically where I should check it
thansk btw

Former User

Again, the starter motor is not protected by any fuse, including the 80A hood fuse. Therefore, as your problem is that the 80A fuse blows, a bad starter wire does not fit.

Start by carefully checking the alternator wires for a short or damage.

What year Civic? Is it bone stock?

pkek925

It 00 Si with a B18c motor swapped into it, Nothing really done upgraded that would equal electrical modification. This just randomly started occuring but had no probs for the last year.

Former User

The large white alternator wire runs between the alternator and the hood fuse box. Check it for a short to body ground. Does disconnecting this white wire at the hood fuse box prevent the 80A fuse from blowing?

pkek925

Going to get another fuse, 3rd ones the charm I hope. Ill check it when I get back, Just disconnect it at the fuse box and try attaching the neg to the battery? Becasue connecting the battery now kills the fuse sometimes rather then me starting the car then it failiing right after.

Former User

Yes

pkek925

Thanks for your help in advance. I got the car to start when I unhooked the alt cable and surprisingly the neg terminal didnt even spark when i reattached it!. Now I know it has somethign to do with the alt so im happy its narrowed down. wondering what it could be , I checked the power wire and it seems to hold a current just fine. any ideas?

Former User

Use a multimeter to check the wire for a short (continuity to body ground). If the wire is fine, then the alternator may have a short.

pkek925

I should check the ground coming from the alt for a short? how would I do that as to the settings on my multimeter and where to connect the other end of the meter (given 1 would be on the ground connecting to the alt.)

Former User

The big white wire from the alternator is not a ground. It's the power output wire from the alternator. Disconnect the white wire at the fuse box and alternator. Use a multimeter to test for continuity to body/engine ground at each end individually. Continuity to ground indicates a short.

JimmyD246

You could check for continuity between the ground and the live from the alternator. This would pick up any shorts. Use the bleep on your multimeter. Then disconnect the live and check again. If you got a short when the live is connected but no short when it is disconnected, you have a alternator problem. If you have a short when the live is disconnected (from the live to ground, not alternator to ground), its a wiring problem. This may not help you find the problem but will help to find a short circuit as explained in the above post.

pkek925

So ill detach the white wire in both ends.
The check the continuity at each end? Thats where im kind of noob. I dont know how to check it, esp if im using the correct setting on the multimeter. And yes I do know that the white line is the power, just not sure how I can check the ground.

Former User

Set the multimeter to read resistance on the lowest scale (e.g., 20-200 Ohms) and then touch one probe to the end of the wire and the other probe to a clean metallic area on the thermostat housing. You should measure infinitely high resistance if there is no short.

JimmyD246

You can also use the sounder on your multimeter, the little speaker symbol. If there is a short, it will bleep

pkek925

I disconnected the white cable from the fuse box, hooked one wire to the end of the wire, then the other to a ground. I was using the 20k ohm setting and it went from 1 to 0.00. when in contact. sound right?

Former User

You used the 20,000 (20K) Ohm scale. Set to the lowest Ohm scale not the highest. Alternatively, use the continuity function, as mentioned above, if you have this function on your multimeter.

JimmyD246

Do you have a analogue or digital multimeter?

Scotty Dosent Know

Good info here.


Reminds me of a story when I was young and dumb. My friend had a fuse that would always pop in his 240 and we could not figure out why. We got so frusterated that we replaced it with a piece of metal and waited. the seat belt sensor started to smoke/flame etc. We pulled it out and problem solved.

DO NOT DO THIS........it was really dumb, was just sharing because its kinda funny

JimmyD246

Ha, I like it! Who needs fuses anyway. Just kepp a fire extinguisher handy!!

pkek925

Nevermind lowest I had was 200 ohms and at that setting it went from 1 (unconnected) to 1.8 with one end on the wire and the other conencted to the ground battery cable

Edit :additionally I have a digital multimeter and not sure if theres a sound function on it. dont see a speaker sign anywehre.

pkek925

haha no im not messing with fire in the car . Had a guy I know that left his rx-7 turbo timer to do its thing but when he came back the whole dash was melted and wiring screwed up from overheating. The mechanic said it was the wiring from the timer and it cost him money out of pocket as insurance wont cover something faulty that he did himself and that they had no idea was put on the car. haha