Getting switched 12v off fuse block?
#1
Nordschleife Master
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Going to rewire all my aftermarket gauges to run off an auxiliary fuse block to clean up the wiring and also avoid any noise from running on the radio circuit. Plus i dont like the idea of having the radio + 4 other gauges running off that one circuit!
After going crosseyed reading the factory wire diagrams last night i think the best bet is to run off the heated seat fuse which is not used on my car. Currently i have my wideband, shift light, boost, oil pressure and water / oil temp run off the radio.. (all electronic gauges). All the gauges were installed at different times so the wiring is really disorganized. I ran through a few other ideas about using the cruise control harness (cruise deleted on my car) and the seat height adjust but this seems like the easiest source for switched 12v.
Anyhow i was wondering if anyone had tapped directly off the fuse block for a power source? If i am reading the wire diagrams right the 12v switched for the drivers side heated seat should be a black / yellow wire on the K connector for the fuse block. Ive never taken the fuse block apart so im not sure what is a good way to tap off that? The not so elegant solution is to just tap off the connector under the seat (it is pin #2 on the seat connector), but seems counterproductive to run a wire all the way back under the dash! Another option is to run it through a standard auto relay and use the switched 12v on the radio as a trigger.. but does not seem worth while to run a line all the way to the battery from the aux. fuse block.
Here is the aux. fuse block i am going to use.
After going crosseyed reading the factory wire diagrams last night i think the best bet is to run off the heated seat fuse which is not used on my car. Currently i have my wideband, shift light, boost, oil pressure and water / oil temp run off the radio.. (all electronic gauges). All the gauges were installed at different times so the wiring is really disorganized. I ran through a few other ideas about using the cruise control harness (cruise deleted on my car) and the seat height adjust but this seems like the easiest source for switched 12v.
Anyhow i was wondering if anyone had tapped directly off the fuse block for a power source? If i am reading the wire diagrams right the 12v switched for the drivers side heated seat should be a black / yellow wire on the K connector for the fuse block. Ive never taken the fuse block apart so im not sure what is a good way to tap off that? The not so elegant solution is to just tap off the connector under the seat (it is pin #2 on the seat connector), but seems counterproductive to run a wire all the way back under the dash! Another option is to run it through a standard auto relay and use the switched 12v on the radio as a trigger.. but does not seem worth while to run a line all the way to the battery from the aux. fuse block.
Here is the aux. fuse block i am going to use.
![](http://img.photobucket.com/albums/v120/TechnoDuck/My%201988%20Porsche%20944%20Turbo/IMG_7644.jpg)
#2
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I use my heated seat circuit for just that purpose! The wires are conveniently there in the loom behind the center console. There's also a nice ground wire...
#3
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Van, thanks for the tip. Do you remember if it was indeed the black / yellow wire on the seat harness? Hopefully this will be the last time i need to pull this damn console apart.
#4
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I did the same, but I wired it to a relay... then the 30A relay to directly to the battery. I mounted the fuse panel under the glove box.
#5
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That is the exact block I used. I am not sure if there is an 80 amp source from the fuse block. I came off the battery w/ an 80amp fuse to a 75amp relay then to the aux fuse block. It has worked well for me, although I can't recall where I got my switched 12v from.
Here is the thread.
https://rennlist.com/forums/944-turb...ghlight=wiring
hope it helps,
Steve
Here is the thread.
https://rennlist.com/forums/944-turb...ghlight=wiring
hope it helps,
Steve
#6
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No need for anything with that high a current rating. The wideband draws at most 5 amps when warming up and each gauge not even 1 amp. So combined i might see a peak of 8 amps when starting the car up.
Found some 30amp relays in my tool box.. thinking now i may just run the aux. fuse panel through a relay then directly to the battery using the switched 12v at the radio as the trigger.
I hate doing anything involving wiring on these cars and unfortunetley that is what this week is going to be all about.. also need to install the SMT8, boost solenoid and MAP sensor for my Vitesse MAF. While i am at it i am going to switch around the grounds for my wideband to go through the DME / piggyback to avoid any ground offset issues. I figured no better time to just get all the wiring sorted out on the car than now.
This got my thinking, dealing with the wiring on this car would be alot easier if i just get rid of all the carpeting..
.
Found some 30amp relays in my tool box.. thinking now i may just run the aux. fuse panel through a relay then directly to the battery using the switched 12v at the radio as the trigger.
I hate doing anything involving wiring on these cars and unfortunetley that is what this week is going to be all about.. also need to install the SMT8, boost solenoid and MAP sensor for my Vitesse MAF. While i am at it i am going to switch around the grounds for my wideband to go through the DME / piggyback to avoid any ground offset issues. I figured no better time to just get all the wiring sorted out on the car than now.
This got my thinking, dealing with the wiring on this car would be alot easier if i just get rid of all the carpeting..
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#8
Three Wheelin'
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My setup was a bit more complex, I'll take pictures of it tomorrow as it's out of the car currently. It has a constant +12V from the fusebox through a 40amp breaker (overkill) to a relay which then goes to the auxiliary fuseblock. The relay is switched using the same switched power from my knock harness. This whole setup is mounted on a sheet of stainless that I bolted to the cruise control brain. I then have a barrier strip for grounds mounted a few inches away on the plastic cover over the clutch. Gives me a nice place to add/remove electronics at will without much effort and no cutting on the stock harness.
#9
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I like to use a fuse tap, like this:
![](http://img.tomshardware.com/us/2006/06/20/rolling_your_own_car_pc/carpc_addafuse.jpg)
![](http://img.tomshardware.com/us/2006/06/20/rolling_your_own_car_pc/carpc_fuse_attach.jpg)
They're normally limited to around 20A, but that sounds as though it would do you fine. They're all over eBay, and likely even Radioshack...
![](http://img.tomshardware.com/us/2006/06/20/rolling_your_own_car_pc/carpc_addafuse.jpg)
![](http://img.tomshardware.com/us/2006/06/20/rolling_your_own_car_pc/carpc_fuse_attach.jpg)
They're normally limited to around 20A, but that sounds as though it would do you fine. They're all over eBay, and likely even Radioshack...
#10
Nordschleife Master
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pointflex, i was thinking about doing it this way and just connecting it to the heated seat fuse so i dont need to cut any of the wiring on the harness. Its funny.. my car is so heavily modified yet i still hate making any changes to the original wiring on the car
. I always say 'well maybe i want to put it back to stock someday'...yea like that's ever gonna happen!
![Smilie](https://rennlist.com/forums/images/smilies/smile.gif)
#11
Nordschleife Master
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pointflex, i was thinking about doing it this way and just connecting it to the heated seat fuse so i dont need to cut any of the wiring on the harness. Its funny.. my car is so heavily modified yet i still hate making any changes to the original wiring on the car
. I always say 'well maybe i want to put it back to stock someday'...yea like that's ever gonna happen!
![Smilie](https://rennlist.com/forums/images/smilies/smile.gif)
![banghead](https://rennlist.com/forums/graemlins/banghead.gif)
The dude that owned my car before me should be drug out and shot for the stupid wiring he did on my car. I'm talking separate hot wires for every single thing. No looms, no zip ties, no heat shrink....
Wiring isn't difficult, but it can be time consuming. Though, cleaning up after a fire takes a lot more time, than using heat shrink and zip ties.
Trying to find a short can be made easy, when the wiring is done correctly.
Wiring is a pet peeve of mine..... I just want to scream when I see stupid **** people do for their "kick ***" stereos, and gauges... Also, 30A is way more than enough for an extra fuse block. V1, WBO2, Gauges, EBC....whatever, all together shouldn't ever run over 20A. The massive fuse panel we used to put under the seat of the state patrol cars, which ran the laser, radio, lightbar, shotgun rack.....everything on a cop car, was only 50A
#12
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Thought about it and i am just going to use the add a circuit fuse holder. Looked at the fuse box and i can easily run a wire into the cabin from there, works out perfectly because i wanted to put the aux. fuse block where the cruise control unit used to be by the hood release. This way i can always bring it back to stock...
.
This is some of the wiring i had to deal with a few months ago when i installed the gauges in the console. I seriously want to punch whoever installed the radio in this car in the throat because they did one of the ****tiest installs ever. Wire nuts, and in some instances just electrical tape holding everything together. I cleaned the wiring up a few months ago but its still a mess. Just bought a new Alpine deck to replace the old Sony one i have now.
![Big Grin](https://rennlist.com/forums/images/smilies/biggrin.gif)
This is some of the wiring i had to deal with a few months ago when i installed the gauges in the console. I seriously want to punch whoever installed the radio in this car in the throat because they did one of the ****tiest installs ever. Wire nuts, and in some instances just electrical tape holding everything together. I cleaned the wiring up a few months ago but its still a mess. Just bought a new Alpine deck to replace the old Sony one i have now.
![](http://img.photobucket.com/albums/v120/TechnoDuck/My%201988%20Porsche%20944%20Turbo/IMG_7648.jpg)
#13
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Here is the DME wiring the PO passed on to me ![EEK!](https://rennlist.com/forums/images/smilies/eek.gif)
![](http://refresh951.com/wiring.jpg)
I spent ALOT of time cleaning this up. I hate working down in that hole. It seems like no matter what I am doing I need to do something down there.
![EEK!](https://rennlist.com/forums/images/smilies/eek.gif)
![](http://refresh951.com/wiring.jpg)
I spent ALOT of time cleaning this up. I hate working down in that hole. It seems like no matter what I am doing I need to do something down there.
#14
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Pin A22 in the fusebox has power when the key is in the start and run position. That is the connector block that doesnt have a plug block in it. You can use a female spade connector (heat shrink it so it doesnt short). A22 is not fused though which is the only problem with it.
#15
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Its going to be very therapeutic for me tomorrow to cut the entire radio harness with the Sony connector out of the car..
. Problem is the fool who installed it cut the wiring at the factory connector aswell, so i cant just plug and play the new radio in with the adapter. Also the speaker wiring was completely hacked up where they tried to strip the wiring in the center (without removing the connector.. half the copper core on a few of the wires is missing. Hopefully i wont need to cut too far back.
Thankfully my main engine harness was untouched..all that is there now is my hack job of an install for the fuel injector resistors, shift light plus a mess of vacuum lines for my boost gauge and boost controller..
![Smilie](https://rennlist.com/forums/images/smilies/smile.gif)
Thankfully my main engine harness was untouched..all that is there now is my hack job of an install for the fuel injector resistors, shift light plus a mess of vacuum lines for my boost gauge and boost controller..
![ducking](https://rennlist.com/forums/graemlins/icon107.gif)