A problem with fuses - help!

[saracen]

Hello - we're hoping someone can help out a couple of puzzled mechanical novices. It's a bit of a long story, but I thought best to say the lot in case there is a clue in there somewhere...
The old Bongo has been playing up a bit recently. It all started with a freezing night in Scotland (in mid August!), which seemed to distress the glowplugs, and make starting in the morning a bit hit and miss. However, a new battery - long needed - and glowplugs have sorted all that out. However, when trying to get the beast (meant affectionately...) started to go to the garage for this work, we managed to start it with a dash of magic starting spray, but it then cut out entirely after about a minute as I was reversing out of the drive. A really helpful breakdown mechanic (after blenching slightly at this hitherto unknown vehicle's innards) isolated the problem as a fuel switch being turned off, the fuse having blown. He replaced the fuse with the expectation that all would then be well.
Two days later - Bongo now back from garage with new plugs and starting once again like a dream - the same thing happened while reversing - again, the first start of the day. Old hands at this, we replaced the fuse ourselves and got going again. However, we clearly don't want this to just keep repeating. It has only happened these two times - both times during a substantial reverse, the odd bit parking or whatever doesn't have any effect thank goodness (to date at least). Also, with a lot of work in the garage this year, we'd rather keep costs down than send the Bongo in for a full in-depth investigation of the electrics...
So, does anyone have any ideas? Is this something we could fix ourselves, or at least could anyone put a name to the problem, so that I can go to the garage with a plan of action?
Really grateful for any advice - I've been amazed (and even learnt a bit) at all the knowledge available here, so do hope someone can help!
Cheers
Gill

[widdowson2008]

I'm surprised that one of the techies hasn't replied to this as yet
As a non technical sort of bloke, and from what you are suggesting, this has only happened when reversing, and it is the same fuse that has blown on each occasion. So is it suggests that the circuit this fuse is protecting is being overloaded? A short circuit or faulty reversing switch? (I will get shot down in flames but it may wake the techies up )
Don't despair, I am sure someone will come along shortly with a few things to look for and helpful comments. Kirsty will be trawling through circuit diagrams as I type)

Question you will be asked is 'whereabouts are you?'

[saracen]

thanks! I'm in North Yorkshire...

[widdowson2008]

Don't know if this will help, but in the absence of owt else it may...........
http://www.igmaynard.co.uk/bongo/forum/ ... se#p136840

[missfixit70]

This is one for G8DHE, he's the man for the circuit diagrams
What fuse is it you're replacing, ie what number, where is it, what size?
This a strange one I'm just wondering if something was disturbed when the glowplugs were replaced, especially if short ones were put in where there were long ones originally.
If you update your profile to include your location by clicking on "User control panel" top right, it will show up on every post & help peole to point you at local help or offer local help

[g8dhe]

Just composing what questions to ask when low and behold Kirsty has asked them! Main one is which fuse are you replacing and which location (Under dashboard by knee or under bonnet if so in which box) ? Also which year is the vehicle ?

[missfixit70]

Now that's spooky, it's like a techie tag team

[saracen]

impressive teamwork folks... It's a fuse in the dashboard (by knee) and it's number 9 on the diagram in the factsheet, 15 amp, described on the factsheet as 'engine management system'. The vehicle is N-reg 1995.
Don't think it can be the glowplug replacement as it first happened before they were replaced. And then again after. Could it be anything to do with getting the new battery? It happened after battery, but before glowplugs.
I'll update the profile - thanks for the tip.
And thanks generally - look forward to finding out more! meanwhile, we're well stocked up on fuses...
Gill

[g8dhe]

Right - to be honest I'm not sure that the diagrams are going to be a lot of help as the ECU feeds many points and the diagram of the internals of the ECU isn't provided. However, one thing does strike me as being important to check is Fuse 1 is often moved over to the L/B when its fitted and Fuse 1 is directly above Fuse 9 in the panel -So drop the fuse panel out and make sure that nothing has been left amiss when the L/B was fitted and the Fuses transferred across. Diagrams below click the thumbnails for full size versions.


Can anyone identify what the acronym FICD stands for its associated with some solenoids similar to the EGR ones? I'm thinking along the lines of Fuel Injection Cutoff Device but might be barking up the wrong tree but it might identify a possible point to look at as the fuel cutoff was involved in the problem ?

[missfixit70]

A short circuit or faulty reversing switch?

As this only seems to be happening on a long reverse, it does suggest that this could be along the right lines. I don't suppose you cut or disconnected the feed to the reversing beeper recently did you? http://www.igmaynard.co.uk/bongo/forum/ ... =3&t=34605 Just wondering if this could be shorting out?

[saracen]

Hi Kirsty - that makes sense actually as the reversing beep was sounding wierd... and then stopped working... I will check this out. Excuse my gross ignorance, but where would the reverse beep be controlled from? We haven't done anything to it that we know of, but the problem might be there - is there something we can do to check this out or make sure that it is as it should be?
I don't have a leisure battery and am terrified by the diagrams, pathetic I know. But fuel cut-off is involved in the problem so that may well be important as well...
For now, I'm thinking the reversing is the important factor, so - with help? - I'll try and check that out?
Thanks as ever...
Gill

[g8dhe]

Yes that's quite possible the gear stick is a simple switch which carries the 12volts from that fuse to the ECU, from the "R" position of the switch it feeds the ECU, the alarm buzzer and the two reversing lights directly - might be worth checking to see if the reversing lights are OK it might be as simple as one of the wires being trapped or even a faulty socket/bulb.

Final part of the engine management diagram, the alarm buzzer and reversing lights;

Links 24 and 25 go to these pages.

[missfixit70]

The link I posted above points you at a few threads regarding disconnecting the beeps, which may help in the fault finding process. I was wondering about the reverse lights, have they been modified at all for one of them to become a foglight? that could be shorting somewhere?

[bigdaddycain]

What a curious problem! I wonder if the inhibitor on the gearbox selector is out of adjustment? (or cable has stretched?) Maybe it's not quite in "R", and is slipping into "P" enough to cut the engine, but not enough to engage the pawl in the gearbox?

[widdowson2008]

What a curious problem! I wonder if the inhibitor on the gearbox selector is out of adjustment? (or cable has stretched?) Maybe it's not quite in "R", and is slipping into "P" enough to cut the engine, but not enough to engage the pawl in the gearbox?

As a non-techie, I havn't a clue what this means and am a bit confused as to how it could cause the fuse to blow.
From what saracen describes, it doesn't sound as if he (she) has a gear selection problem. Shouldn't we be looking for the cause of a blown fuse. (or have I missed something? - again )