1: my tail lights ( not my brake lights ) have stopped working
2: I read somewhere that you should directly earth to the chassis new gauges and stereos rather than run them through the radio wiring earth. I done this vis the 2 bolt hole that are in the support bar right above the stereo. I Grounded my EVC IV, my stereo head unit, and my boost gauge and another multi function gauge ive got. Now im getting huge battery drain and it goes flat after a day or two. *Note* all my power to the units comes from the 12v ignition wire from my stereo feed ( probably overloading this but thats besides the point, unless of course it melted a wire somewhere andis earthing out )

anyway. your help please. Is what ive done ight?

 

The taillights are on the same fuse as gauge lights. If they're not working too then check the 15A ILLUM fuse in the cabin fuse box. If the fuse is okay then a faulty headlight switch is a common cause of this problem.

There is no stereo ground wire, the stock stereo is grounded through the metal frame that supports it. So what you did to ground your extra electronics is correct. Feeding them all of one power supply isn't so good, but that won't be causing the battery to drain. A damaged wire that's grounded won't cause this either, it would simply blow a fuse.

With the ignition off, disconnect the battery's negative terminal and connect a DMM between the the clamp on the wire and the terminal itself so that the DMM is inline with the battery. Sett the DMM to DC amps and you should see how much current is flowing. Normally it'd be close to zero but if something's draining the battery then you should get a reading. Now start pulling out the fuses in the cabin fuse box one at a time. If the current drops to near zero then one of the systems protected by that fuse is the culprit. Then you just have to inspect those systems to find the cause.