rb20 blowing "meter" fuses

[Nick51]

My rb20 keeps on blowing the "meter" fuse under the dash. It controls the tach/cluster, seatbelts and the heater/blower. The little red battery light on the cluster comes on but barely illuminates. Then my batt voltage reads under 12 when the car is on and it usually reads around 13.9v. It calls for a 10a and I have tried putting in 15 20 and even a 25 but just keeps blowing them. It has done this before but half the time I would just pop in another be fixed but its at its worse now. I tried wigglin the wires somewhat but nothing.

I also noticed the relay box on the drivers side in the engine bay, the relay that says "ACC/ DIFF OIL" the prongs on the board itself look all discolored like it has seen some heat along with the plastic is a little discolored. Could that have anything to do with it?

Any ideas what my problem could be??
Modified by Nick51 at 7:11 PM 2/17/2008

[Carl H]

something is malwired, check your wiring.

[Nick51]

where exactly should I should start and should I be looking for a spliced/bare wire?

[Nick51]

so I dissconected the neg terminal and hooked up a test light to the neg wire and touched the neg post with the probe and the light lights up for less than a second and fades out?? Then after a few seconds of no contact and I would do the same thing, touch the post for a second, it would come on very feint and then go out?

What would be causing this, do I have a short somewhere