Radio shuts off when headlights are on

Check to see where they hooked to get power supply. Sounds like they hooked to relay that controls the lighting and is tripping the breaker/relay. Try running wire to the accessory side of switch or just fuse and run power to the battery to check.

How about loss of negative frame ground ? You could hook a jumper cable between battery negative and body metal to test this. You have ground to engine so starter and alternator work.

Sounds like a body ground, I would start there.

DUDE!!! Installing a new ground Worked for these symptoms ive been having for MONTHS! Dim headlights, pressing brake would shut off radio, turn signal slow and non blinking, also would shut down radio, dash lights dim and gauges FREAKING OUT!!! Process CHEAP AND EASY!

when you turn off the radio and subs does the car start?

do other things work in the car like headlights indicators brake lights

i sugest you turn off the radio and start car or unplug the subs from the battery and try

RE: Radio

If you mean the radio doesnt retain the memory presets and clock when you shut the car off or turn the key to the 0 position

that could mean that the yellow wire was not connected to the red or hot/positive lead when the radio wiring harness was connect

if this worked before and now it does check the main fuse box
also some radios have a inline fuse connected on the radio wiring harness (behind radio so you'll have to remove it to check, same thing with checking that the yellow wier is connected)

not sure what you mean by "electrical problem headlights"
some cars shut off the electrical current to the head lights (only power to running/park lights) when the ignition is shut off or the key is at position 0

your stereo has been wired up to the lights and when you turn on the lights the stereo cuts out. you need to get the stereo rewired

maybe you pushed the high beams on. if its not that check the dimmer switch

possibly the dimmer switch on the floor? happened on my 91 half ton dims didnt work but brights did and then they cut out altogether. a little water goes a long way

check your ground on the radio......... the feed from the lights will test as a ground and the radio will use this as a circuit and turn on the lights. been there done that what a nightmare