Keep blowing indicator fuses - why?

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Sharkojoints
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Keep blowing indicator fuses - why?

Post by Sharkojoints » Wed Apr 12, 2017 7:23 pm

My Bongo indicators stopped working today. The flasher unit - grey box bottom right of driver's footwell - clicks fast, but no green dash lights, no indicator lights and no hazard lights.

Fuse nr 2 - top row, second from left, 10A - blows the moment either the indicator switch is activated or hazard button pushed. Fuse 11 - this one:

Image

is intact.

I've checked all bulbs which test fine. The system blows the fuse even with all indicator bulbs removed.

My next thought is a faulty flasher unit. Any ideas please?
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g8dhe
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Re: Keep blowing indicator fuses - why?

Post by g8dhe » Wed Apr 12, 2017 8:00 pm

Is it left or right indicators that are causing the problem or either side?
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Sharkojoints
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Re: Keep blowing indicator fuses - why?

Post by Sharkojoints » Wed Apr 12, 2017 8:46 pm

Either side, as far as I can tell, but it'll have to wait until tomorrow for a definite answer. Certainly blows with either hazard switch or RH indicator stalk.
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Re: Keep blowing indicator fuses - why?

Post by g8dhe » Wed Apr 12, 2017 10:27 pm

The most common problem is faulty wiring at the lamp socket, wires get damaged and short to earth or an earth wire, or possibly corrosion products in the base of the lamp socket, however that will only affect one side. But faulty modules haven been known as well, and could affect both sides.
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Sharkojoints
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Re: Keep blowing indicator fuses - why?

Post by Sharkojoints » Thu Apr 13, 2017 9:08 am

Thanks.

So, it's the RH side which is blowing the fuse. LH works fine.

Also, on removal of the bulbs, my multimeter finds continuity between the centre + and the outer earth terminal of the holders - should this be?

No obvious issues, faults or problems with the bulb holders: all clean and undamaged.

Which takes me back to a suspect flasher unit diagnosis?
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Re: Keep blowing indicator fuses - why?

Post by g8dhe » Thu Apr 13, 2017 9:58 am

Before doing the continuity test unplug the loom from the module, just to make sure that the continuity your seeing isn't from the flasher module itself! If it still shows a short then its down to the wiring, most often problems develop in the vicinity of the connectors for the bulb itself, unless the wiring loom has been pinched some where from previous work or welding work that has melted the insulation.
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WestyK
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Re: Keep blowing indicator fuses - why?

Post by WestyK » Thu Apr 13, 2017 11:28 am

Hi

Still quite new to Bongo ownership but have some experience with car electrics.

First question. Is there a towbar fitted. If there is that would be my first thing to check as this wiring is likely to be the week link on this. Could just be a broken wire in the socket or where the loom has been joined to.

You could also see if the the fuse still blows without the bulb fitted. Its rare but not unknown to have a bulb short out

Other that that the advise given by others is sound.

Hope that's some help
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Re: Keep blowing indicator fuses - why?

Post by Sharkojoints » Thu Apr 13, 2017 12:21 pm

Thanks guys.

Fished a s/h flasher unit from a Bongo at the scrappies this morning, and all is now working again. I took the black cover off the bottom of the old one, and nothing's obviously burnt out or similar, but there you go.

I'd have gone for trailer electrics too, but they checked out fine, and I fitted them myself this year so know how they're wired. I also had a stop n tail bulb shorting out that circuit last year, which was a bulb which looked outwardly fine, so the bulbs were my first working diagnosis until they all tested OK.

For reference, there was still continuity between the + and - in the bulb sockets even with no flasher unit fitted. Weird.

Thanks again for your help! =D>
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Re: Keep blowing indicator fuses - why?

Post by Bob » Thu Apr 13, 2017 12:39 pm

Glad you're sorted, and thanks for the update. :)
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Re: Keep blowing indicator fuses - why?

Post by WestyK » Thu Apr 13, 2017 1:28 pm

Great news.

Sorry if I was a bit "teaching Granny to suck Eggs" with my suggestions wasn't sure on your own experience but sounds like you know the electrics quite well.
Always good to hear what the fault was for future ref.

In the short time i have been here its already been a great help, its an excellent resourse so just trying to put a little bit back.

Cheer
Ian
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Re: Keep blowing indicator fuses - why?

Post by g8dhe » Thu Apr 13, 2017 2:13 pm

When checking for continuity you do of course need to remove all the lamps - otherwise your seeing the other lamps as a short!
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