What does this 20A fuse do and why would it pop?
What does this 20A fuse do and why would it pop?
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zed4

Original Poster:

7,248 posts

252 months

Sunday 22nd December 2013
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Car wouldn't start this morning, just clicked, then nothing. Found this fuse was popped. What does it do?

MADMAX2

2,336 posts

224 months

Sunday 22nd December 2013
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is it the hot start bypass fuse that has gone?

Sardonicus

19,451 posts

251 months

Sunday 22nd December 2013
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Judging by the red wire coming off that fuse board spur that fuse blown maybe part of a hot start kit/mod you need to identify if the fuse just fatigued or you have more sinister problems my home made kit work just fine with a 15a fuse for the last 4 years scratchchin

zed4

Original Poster:

7,248 posts

252 months

Sunday 22nd December 2013
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Sorry for the rushed post this morning! Yes, I did mean the inline fuse in the wiring. I think it is to do with the hot start kit the previous own fitted.

For some reason my car wouldn't start this morning. It just clicked when I turned the key to start. Battery was fine. There was a hell of a storm here last night and it was left outside, so maybe the damp caused the starter motor to stick. After a couple of attempts it wouldn't even click, I think this was when the fuse popped.

Anyway, I bump started it down the hill and changed the fuse and it was fine for the rest of the the day, started every time. Hopefully it was a one off, but maybe I'll look at changing the starter or solenoid in the future if it happens again.

MADMAX2

2,336 posts

224 months

Sunday 22nd December 2013
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you dont need to change the starter or solenoid just check the connections on the hot start kit. correct me if im wrong but the fuse wouldnt blow because of the stater or solenoid unless there was an earth issue with either of them

zed4

Original Poster:

7,248 posts

252 months

Monday 23rd December 2013
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Ok, so an update.

After replacing the fuse yesterday and getting it started, it was perfect for the rest of the day. Started whether it was hot or cold and I did a few mile yesterday, stopping and starting quite a lot.

Overnight we had very heavy rain again, just been out to check it will start up ok and it's clicking but not turning over, again. I only tried it a couple of times. Fuse didn't pop.

I had a fiddle around, checked the fuse and the connections and it all looked ok. Tried it again and it turned over and started fine. All very strange. So it's working ok now, at the moment. Switched it off and fired it up a few times, each time was perfect, turned over really fast and started straight away each time. So it was just the first couple of times it wouldn't start.

I think I'll have a better look at all the connections when I'm home from Cornwall. Could the damp be causing the starter motor to stick? The solenoid is obviously clicking in (except for the time the fuse popped), it's just not turning over.

Or do you think there's a problem with the main battery cables to the starter? The battery terminals are tight and good.

Sardonicus

19,451 posts

251 months

Monday 23rd December 2013
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zed4 said:
Ok, so an update.

After replacing the fuse yesterday and getting it started, it was perfect for the rest of the day. Started whether it was hot or cold and I did a few mile yesterday, stopping and starting quite a lot.

Overnight we had very heavy rain again, just been out to check it will start up ok and it's clicking but not turning over, again. I only tried it a couple of times. Fuse didn't pop.

I had a fiddle around, checked the fuse and the connections and it all looked ok. Tried it again and it turned over and started fine. All very strange. So it's working ok now, at the moment. Switched it off and fired it up a few times, each time was perfect, turned over really fast and started straight away each time. So it was just the first couple of times it wouldn't start.

I think I'll have a better look at all the connections when I'm home from Cornwall. Could the damp be causing the starter motor to stick? The solenoid is obviously clicking in (except for the time the fuse popped), it's just not turning over.

Or do you think there's a problem with the main battery cables to the starter? The battery terminals are tight and good.
Check that the small terminal going to the starter/solenoid is secure and corrosion free, you will however have to get under the car for this frown

zed4

Original Poster:

7,248 posts

252 months

Monday 23rd December 2013
quotequote all
Sardonicus said:
heck that the small terminal going to the starter/solenoid is secure and corrosion free, you will however have to get under the car for this frown
Ok, thanks mate. I'll get it on axle stands when I'm home to check all the connections as a matter of course.

JonathanT

880 posts

314 months

Monday 23rd December 2013
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I think this protects the feed to the solenoid on the starter motor?

Not the same problem, however the 20A fuse on my hot-start mod also popped when the main feed from battery to starter motor broke through metal fatigue. Mr RAC who came out concluded that in this state, the starter motor was trying to draw full cranking current through this fuse/solenoid feed which is why it was popping.

He remade the battery connection and all has been fine for the last couple of years.