Found the short circuit! any suggestions now ?

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planet Bongo

Found the short circuit! any suggestions now ?

Post by planet Bongo » Mon Oct 24, 2011 11:52 am

Hello everyone,

Finally I managed to find the short circuit (well i hope so) that probably caused the fuse 15A (under the bonnet) to blow from time to time, causing my side lights, number plate and dashboard lights to go off.

The diagnostic shows the fuse 10A (number 1 in the chart) under the dashboard. and that is the CABIN lights. Any suggestions on how to troubleshoot this problem, i will appreciate any input.

Thanks
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Re: Found the short circuit! any suggestions now ?

Post by jaylee » Mon Oct 24, 2011 1:06 pm

planet Bongo wrote:Hello everyone,

Finally I managed to find the short circuit (well i hope so) that probably caused the fuse 15A (under the bonnet) to blow from time to time, causing my side lights, number plate and dashboard lights to go off.

The diagnostic shows the fuse 10A (number 1 in the chart) under the dashboard. and that is the CABIN lights. Any suggestions on how to troubleshoot this problem, i will appreciate any input.

Thanks
Both these service two different circuits.... The 10A for the courtesy lights also have something to do with radio memory & strangely on my diesel, the engine management. The coil light flashes with this fuse pulled out! I surmise it could do with the ECU memory & control over the scavenger fan when the engine ignition is off!! (But, the last bit is just a guess.)

The fuse going under the bonnet maybe down to dodgy wiring on an aux switch or circuit like the rear fog??
Have any capless bulbs been replaced recently, like for instance the one in the panel behind the drivers seat over the rear heater control or rear number plate lights...?
The contacts in the bulb holder can get sort of crushed causing a short if not inserted properly!!

Hope this helps?!
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Re: Found the short circuit! any suggestions now ?

Post by g8dhe » Mon Oct 24, 2011 3:01 pm

planet Bongo wrote:Finally I managed to find the short circuit (well i hope so) that probably caused the fuse 15A (under the bonnet) to blow from time to time, causing my side lights, number plate and dashboard lights to go off.

The diagnostic shows the fuse 10A (number 1 in the chart) under the dashboard. and that is the CABIN lights. Any suggestions on how to troubleshoot this problem, i will appreciate any input.
Can you explain what you found as the two fuses are not related at all ?

The 15Amp TAIL fuse controls the side lights (TNS) via the relay;


And the 10 Amp controls the cabin lights;
Geoff
2001 Aero V6, AFT, full side conversion.
planet Bongo

Re: Found the short circuit! any suggestions now ?

Post by planet Bongo » Mon Oct 24, 2011 3:17 pm

its the 15A under the bonnet that keeps blowing. diagostic shows short circuit in 10A ( light cabin). any clue?


( i run the diagnostic using Basic circuit tester, a screwdriver with a lead and bulb, connect it to the battery and start pulling the fuse one by one untill the light on the screwdriver went off)
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Re: Found the short circuit! any suggestions now ?

Post by 321Away » Mon Oct 24, 2011 3:26 pm

do you have the automatic lights on system? the 15A under the bonnet switches on the dash clock lights too and wondering where there could be a connection??

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Re: Found the short circuit! any suggestions now ?

Post by g8dhe » Mon Oct 24, 2011 4:31 pm

planet Bongo wrote:its the 15A under the bonnet that keeps blowing. diagostic shows short circuit in 10A ( light cabin). any clue?
There are TWO 15 Amp fuses under the bonnet the TAIL fuse and the FOG fuse, we are talking about the TAIL fuse aren't we (its the only one that would affect the TNS lights);
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the FOG fuse is Image
planet Bongo wrote:( i run the diagnostic using Basic circuit tester, a screwdriver with a lead and bulb, connect it to the battery and start pulling the fuse one by one untill the light on the screwdriver went off)
Did you have a car door open ? As that will cause several light circuits to operate (if the light switches are in the "door" position or in the "On" position) and removing the;
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fuse will then cause the lights to go out and the basic tester to stop glowing as well!
That fuse controls MANY different circuits;
Fuse X03-8 - 10 Amp
Page     Circuit
30 Engine - Control System - WL-TAT
32 Engine - Control System Ignition - FE-E
38 Engine - Control System Ignition - J5-DE
82 Air conditioning - Auto A/C Control System & Heater - WL-T, FE-E, J5-DE
90 Chassis related - EC-AT Control System - FE-E, J5-DE
100 Interior lighting - Cargo Room & Spot Lights - WL-T, FE-E, J5-DE
102 Accessories - Audio System - WL-T, FE-E, J5-DE
104 Accessories - Car Navigation System - WL-T, FE-E, J5-DE
108 Body - Power Door Lock System - WL-T, FE-E, J5-DE
116 Body - Auto Free Top - WL-T, FE-E, J5-DE
124 Body - Sound Warning System - WL-T, FE-E, J5-DE
Geoff
2001 Aero V6, AFT, full side conversion.
planet Bongo

Re: Found the short circuit! any suggestions now ?

Post by planet Bongo » Mon Oct 24, 2011 5:30 pm

Its the TAIL fuse. And yes, passenger door was open when i was running the diagnostic :oops: .

ok, will run the test again :evil: . thanks for all your help.
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Re: Found the short circuit! any suggestions now ?

Post by g8dhe » Mon Oct 24, 2011 8:19 pm

What is it your looking to identify with your basic tester ? Its unlikely to show up any intermittent shorts with the van standing still and no vibration taking place. Its not that common to find shorts on the wiring looms either (they do occur but normally its breaks in the wiring!) Most shorts will be due to faulty bulbs and termination of wiring at sockets etc. so your better taking the bulbs out and giving them a good examination both the bulbs and the sockets (from the rear) or simply replacing bulbs if they look at all suspect.
Geoff
2001 Aero V6, AFT, full side conversion.
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Re: Found the short circuit! any suggestions now ?

Post by jaylee » Mon Oct 24, 2011 9:34 pm

g8dhe wrote:What is it your looking to identify with your basic tester ? Its unlikely to show up any intermittent shorts with the van standing still and no vibration taking place. Its not that common to find shorts on the wiring looms either (they do occur but normally its breaks in the wiring!) Most shorts will be due to faulty bulbs and termination of wiring at sockets etc. so your better taking the bulbs out and giving them a good examination both the bulbs and the sockets (from the rear) or simply replacing bulbs if they look at all suspect.
jaylee wrote:
The fuse going under the bonnet maybe down to dodgy wiring on an aux switch or circuit like the rear fog??
Have any capless bulbs been replaced recently, like for instance the one in the panel behind the drivers seat over the rear heater control or rear number plate lights...?
The contacts in the bulb holder can get sort of crushed causing a short if not inserted properly!!


Hope this helps?!
I'm with Geoff on this...

If bulbs haven't been pushed in squarely with the holder types highlighted above, instead of the positive & negative terminals sitting at the contacts on the bulb, they can get crushed to the bottom of the bulb holder & possibly touching.. The contacts are actually quite fragile!! A tell tale sign might be a looser than normal bulb..?
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