Noobie with wiring problem

Installing a CD player in my 94 toyota turcel.  I'm used to working with audio in a pro enviroment for years (audio and produciton company) but car audio always throws me a loop.  Here the current loop....

I wanted to check all my wires with a meter before installing/crimping to make sure I've got the right information off the diagram (that I got here).  When I try and read the current between my ignition (grey) and my ground (brown) connection with my meter, the fuse blows every time.  I'm worried that I've got a major wiring SNAFU somewhere in the dash.  Any recommendations?  Any workarounds?

I think you are blowing the fuse because you are shorting the 12v+ to the 12v- by 'checking for current' between the two.

Ofcourse you will blow a fuse.....current is pretty much infinite with consideration of the probes and resistance in the meter. Most meters I know of will measure 2A or 10A scale unfused. You are lucky you haven't blown up your meter yet.

Try checking voltage between the two points, 20 volt range or equivelent. If you read something aroung 12.6-14 volts it should be fine.

Yes the chassis is negative in autobiles, most of them anyways. If the battery is connected well enough to the body, there is no need to run negative wiring all the way to the battery.

I don't understand flynntech.  I was in fact doing what you suggested in the second part of your post.  That is I was in the 20 volt range and I did in fact after another attempt get a health reading of around 13.  I don't seem to be having the fuse blowing problem any more. Wich worries me. I hate intermitant problems.

Stevedart: the fuse that was blowing was for the radio.  So it wasn't too supprising.  Just not sure why I blew it several times with a meter and now its fine.

Another problem I've encountered. (imagine that)  After getting a healthy reading finally with the meter for the +12v switched.  I went on to check the +12v constant and found no current at all.  So, as of now, I've just got an old, really aweful radioshack tape deck in there (wich doesn't have any memory so it doesn't matter that the +12v constant doesn't work.) I put this in incase I do have an intermittent grounding problem. But I do want to get this sorted out and put the CD head in there.

Is running a new line for the +12v constant a huge pain in the ass (for a noobie)?  What other problems could I have that would make it appear that I have a dead +12v constant?

You guys are great, thanks so much for you help.

signed: 

nOobIE

Thanks for clearing that up, I was confused myself. From the way you wrote it, I thought for sure you were connecting the two together with your multimeter in the AMPS scale...and POOF!! blowing the fuse everytime, anything is possible!

I think a wire is pinched and shorted to ground somehow, as has been mentioned already. Just don't use those wires, it works better with a separate 10 awg wire from the battery anyways.

Not hard at all, infact take 'PITA' out of your vocabulary all together and that alone will lift you clear out of the noobie catogory.

Get yourself an ATO 'add-a-fuse' kit or equivelent, some 10 awg, maybe 12awg, but 10 is better to work with. crimp a ring terminal on the end and put the fuse holder together, solder if you can, loom it, tape it, zip-tie it, pull the wire through a rubber gromet not being used or out of the way in the firewall. The clutch cable or throttle cable, even the main wire harness if you are VERY careful. I usually tape it to a long screwdriver and shove it through the rubber, I haven't actually drilled through a firwall in a long time.

tap into the acc under the steering colum or someplace at the fuse panel and run a wire to the HU for that. The color codes are in the vehicle info section.