yes 10A, strange how 10A can melt the .75 gauge wire casing, i did notice in the wiring diagrams that one the light is on it feeds not just to ground but also feeds back to the zke control unit, is this not behind the glove box?
Wiring harness fire, what to do next..?
- Thread starter Dino D
- Start date
I'm not that knowledgable on electrics to comment much (!). If the ZKE is the body control module then yes i think it's there (along with a few others).
the ZKE control unit (according to the wiring diagram is post boot light and before the boot switch to ground, i will try and find a schematic of the inside of the ZKE control unit, if this unit is fed a current post boot light i cant see how it would overload even with a short, however if the ZKE is also grounded when when the boot switch is to ground then it could overload assuming the boot switch also limits current to ground. i will have a dig around.
ok, did this happen after about 16 min driving by any chance?
ohms law.
10amps x 12volts = 120watts. Ever touched a 25watt soldering iron?
however, a 10amp fuse will support 10amps for a period of time before failing. So for a short period, maybe as much as 5 - 10 seconds you might have 150 - 200 watts.
0.75mm wire is only rated at about 8 amps so shouldn't have a 10amp fuse.
A boot lamp is probably only 10watts so a 3 amp fuse would be more than enough.
10amps x 12volts = 120watts. Ever touched a 25watt soldering iron?
however, a 10amp fuse will support 10amps for a period of time before failing. So for a short period, maybe as much as 5 - 10 seconds you might have 150 - 200 watts.
0.75mm wire is only rated at about 8 amps so shouldn't have a 10amp fuse.
A boot lamp is probably only 10watts so a 3 amp fuse would be more than enough.
it doesn't just feed the light, the same fuse is used for 6 other circuits . the current for the boot light is controlled and monitored by the zke control unit and is also on a timer again controlled by the zke unit.
questions are - would an intermittent short reset the timer in the zke and convince it the boot was open? this is likely as it detects the ground when you open the boot
Or could a failure in one of the 6 other circuits fool the logic in the zke and allowed more current to flow to the boot light?
the wire from the 10A fuse is 1.0mm2 but reduces to .75mm2 at the junction for the other circuits (assuming the diagrams are correct).
other circuits or partial circuits are as follows -
interior lights
side light switch and head light switch
ignition switch
left park light relay
zke unit
questions are - would an intermittent short reset the timer in the zke and convince it the boot was open? this is likely as it detects the ground when you open the boot
Or could a failure in one of the 6 other circuits fool the logic in the zke and allowed more current to flow to the boot light?
the wire from the 10A fuse is 1.0mm2 but reduces to .75mm2 at the junction for the other circuits (assuming the diagrams are correct).
other circuits or partial circuits are as follows -
interior lights
side light switch and head light switch
ignition switch
left park light relay
zke unit
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I was driving for over an hour when it happened.
On thing I thought of - I am not sure if the boot properly shut all that time and thus could have left the light on/flickering whilst driving.
Also the headlight we're on (dipped beams).
Interior light was off.
sidelight switch wiring of F33 is 0.5mm. There is just a bit too much running off one fuse and/or cable sizes are just too "economic". But, all cars are the same!
pinkpiggy
Regular Member
Boot light is the trunk interior light or brake light? (sorry, my english isnt perfect so i have a few problems understanding what happened exactly). Do you have coupe or roadster? Is there any chance to avoid this situation? Anyway i am sorry for your "lost", i hope everything is ok at this time after few months/years.
yes trunk light (roadster) , you could fit a low amp fuse to the feed, but as you have a coupe you should be ok.