Major Screw Up - Smoked a Harness
05-29-2006, 03:22 PM
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Major Screw Up - Smoked a Harness
It has often been said that I don't do anything half way, unfortunately that includes screwing up. Did a good one today.
Was re-installing the pod when one of the wires on the emergency flasher switch contacted the steering column mount near the ignition key area. Lots of smoke and at least one red hot wire before I could clear the short. Thought the battery was disconnected. Must have hooked it back up yesterday to check something and forgot to unhook it. Might have helped if I had noticed the interior lights coming on this morning.
Spent the last 3 hours removing dashboard parts and unwrapping wire bundles. It looks like the damage is limited to under the dash. Sections of about 10 - 20 wires will need to be replaced or repaired. Hopefully nothing else got fried in the process.
Will try to post some pics if anyone is interested.
Right now it is "goo-gone" time. All those wires are a gummy mess from the tape. Once that is cleaned up I'll have a clearer picture of the damage.
Was re-installing the pod when one of the wires on the emergency flasher switch contacted the steering column mount near the ignition key area. Lots of smoke and at least one red hot wire before I could clear the short. Thought the battery was disconnected. Must have hooked it back up yesterday to check something and forgot to unhook it. Might have helped if I had noticed the interior lights coming on this morning.
Spent the last 3 hours removing dashboard parts and unwrapping wire bundles. It looks like the damage is limited to under the dash. Sections of about 10 - 20 wires will need to be replaced or repaired. Hopefully nothing else got fried in the process.
Will try to post some pics if anyone is interested.
Right now it is "goo-gone" time. All those wires are a gummy mess from the tape. Once that is cleaned up I'll have a clearer picture of the damage.
05-29-2006, 04:23 PM
#2
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Ouch! - thats going to be painful...
This just reinforces the need to have the battery disconnected - unfortunately Porsche runs quite a few wires in the car that have no fuse protection anywhere - normally not a major problem - but when you tear into things... or if something goes badly wrong and melts wiring looms...
I am actually planning on adding a few very big fuses for insurance - I have the parts... I'm looking at installing an approx 150-200A fuse to the CE panel supply and a couple of smaller ones in the other directly supplied battery wiring (cooling Fans etc). Still working out the details. BTW these are honking big fuses!
Alan
This just reinforces the need to have the battery disconnected - unfortunately Porsche runs quite a few wires in the car that have no fuse protection anywhere - normally not a major problem - but when you tear into things... or if something goes badly wrong and melts wiring looms...
I am actually planning on adding a few very big fuses for insurance - I have the parts... I'm looking at installing an approx 150-200A fuse to the CE panel supply and a couple of smaller ones in the other directly supplied battery wiring (cooling Fans etc). Still working out the details. BTW these are honking big fuses!
Alan
05-29-2006, 05:11 PM
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Oddly enough the wire that is completely toasted is the ground from terminal 31. Makes me wonder if the real problem was in the flasher switch itself.
05-29-2006, 08:49 PM
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Hi Phil, sorry to hear about your Lucas. ahhh I mean Bosch smoke party, lucky its only one fried wire tho there will be others with melted insulation you might make things easier on your self by just cutting the affected wires and adding a piece of heatshrink to the ones with melted insulation and then wrapping them back together with elex tape, solder the cut wires back together, Stan
By the way always disconnect the battery when working on the pod if any switch is removed then it has a good chance of shorting out on the mounting point of the switch and the switch body BTDT
By the way always disconnect the battery when working on the pod if any switch is removed then it has a good chance of shorting out on the mounting point of the switch and the switch body BTDT
05-30-2006, 01:59 AM
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Alan, that 200A fuse will still pass enough current to make the average under-dash wire light up like a light bulb. You know the old saying about how hard it is to make a system idiot-proof... 
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05-30-2006, 03:22 AM
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Dave,
True a lot of bad things can happen at much less than 150A - but a dead short even on a smallish wire will draw quite an instantaneous current. These fuses are supposed to be very fast acting... depends how fast...?
Agree a few small ones may still get fried but the mega-catastrophe may be avoided. I think may car is in pretty good shape electrically - but you never know.
I do think Porsche was a bit lax in a few key areas re: protection. One of the biggest snafus (I think) is that the intended radio supply from the ignition switch is not fused and assumes the fuse is in the radio...
That seems a big bad assumption considering the kind of trained monkeys that install stereo equipment in most places... How many of you have looked in vain for the Radio fuse on the CE panel? - I did...
Anyway just another project on my very long list of TBD's
And there are so many of them to go around... 
Alan
True a lot of bad things can happen at much less than 150A - but a dead short even on a smallish wire will draw quite an instantaneous current. These fuses are supposed to be very fast acting... depends how fast...?
Agree a few small ones may still get fried but the mega-catastrophe may be avoided. I think may car is in pretty good shape electrically - but you never know.
I do think Porsche was a bit lax in a few key areas re: protection. One of the biggest snafus (I think) is that the intended radio supply from the ignition switch is not fused and assumes the fuse is in the radio...
That seems a big bad assumption considering the kind of trained monkeys that install stereo equipment in most places... How many of you have looked in vain for the Radio fuse on the CE panel? - I did...
Anyway just another project on my very long list of TBD's
You know the old saying about how hard it is to make a system idiot-proof...
Alan
05-30-2006, 01:47 PM
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Alan, you may be right about a large fuse blowing fast enough to be better than nothing -- let's hope you never have to find out -- oh, and carry spares, doesn't sound like a common item. Or maybe consider manual-reset breakers...
05-30-2006, 02:04 PM
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Dave,
Standard breakers are usually slow acting - so I'm going to stick with the fuses - they aren't common you are right - and I do have a bunch of spares foirtunately they are fairly cheap (~$3). This is what they look like: the fuse holder is bigger than you might think - about 4-5" long.
Figuring out where exactly to put it - near the jump terminal somewhere ...
Alan
Standard breakers are usually slow acting - so I'm going to stick with the fuses - they aren't common you are right - and I do have a bunch of spares foirtunately they are fairly cheap (~$3). This is what they look like: the fuse holder is bigger than you might think - about 4-5" long.
Figuring out where exactly to put it - near the jump terminal somewhere ...
Alan
