70 Cuda 440 fuse keeps blowing

[ryan1522]

I'm trying to narrow down a few electrical issues.  First is I have no dash lights, road lamps, wiper fluid motor..etc.  All seem to be related to the "accessory" fuse.  The issue is the fuse keeps blowing.  As soon as I turn the key front or back the fuse blows.  Key in and buzzer ok, turn not ok.

I'm thinking it might be a bad ignition switch.  Looked a lots of the wiring and things seem to be ok.  Could it be shorting out inside? 

I'm also getting a really big parasitic battery draw.  Found the alternator to be a good portion but still something else.  Could this also be related?

[Strawdawg]

does not sound like an ignition switch problem to me.

Have you looked at the wiring diagrams and checked each circuit on that fuse for a short?

[ryan1522]

So just for the hell of it I went today and bought an aftermarket ignition switch from Orielly's.  It had a longer black and red wire which I just stuck in the connector.  When I plugged it in at first it seemed to work.  The fuse didn't blow, but then the fuse coming from the starter relay did.  It appears the wire arrangement might be different on the aftermarket vs the OEM. Anyone know this to be true? 

Getting sick of this and can't seem to figure where there is a short.

[JoeGrapes]

I just had the same problem. The accessory fuse controls the two accessory feed plugs under the dash. Each plug has three female holes and is connected to an orange wire. You have a dead short in one of the circuits that are plugged in them. I would unplug all every thing that's plugged into the two feeds. Replace the 20 amp fuse and start by plugging back in one at a time until you get to the one that blows the fuse. In my case I had a pinched wire on my road lamps that grounded out when I turned the key. That told me the short was in the power wire to the road lamp switch.   

[JoeGrapes]

some how when I was putting the steering column back in I pinched the road lamp power wire when I tightened to two nuts that hold the column to the dash frame.