Audio is dead! How to troubleshoot?

[OzzieNorm]

When I bought my ST, the salesman told me that the audio display was not working. He said that he had had the radio working whilst he was driving.

However, there is no sign of power for me.

I have replaced both audio fuses (cabin and engine bay) with known good fuses. Still nothing.
The aerial stays fully retracted; again indicating no power to the audio unit.

When I press the On/Off knob, I hear nothing. Should the be some sort of click?

I have had the dash apart chasing other defects (air only to demist; fan only working on Max). I had the audio unit out and reinstalled it; so, all cables are connected.

Any suggestions as to troubleshooting techniques - before I look to replace the unit?
Thanks.

[04OFF]

What year model are we talking about, assume it "is" the factory head unit (radio), if you can removed the head unit, then get a test light or multi meter, and check you have "2" wires that supply 12+ power when the IGN key is on (one constant ,one switched), then check for a earth wire, and sometimes earthing the chassis of the head unit to earth (just with a bit of wire) can help with bad earth situations.

Some head units will have a fuse on the back and or in the wiring ,most factory ones are in the car fuse box , and or internal inside the head unit itself.

If you have 2 sources of power to the head unit, and a good earth wire, plus try the direct earth onto the chassis of the head unit, and it still does not work, id say its the head unit that is cactus and needs some love (or the bin)

[xtreme patrol]

Simple Fix in 4 steps

Step 1: Remove head unit
Step 2: Throw head unit in the trash
Step 3: Purchase ultra cool double din do everything with gps head unit from ebay or somewhere
Step 4: Install ultra cool headunit with gps

FIXED

No seriously do what 040FF said ....... Still no worky .....Then do this easy 4 step plan

Ive heard of many early GU double din unit doing the exact same thing (Including mine) I used to thump mine and it would work for a little bit LOL

[Cazza]

im having the same headunit trouble i hav even managed to find a 2nd hand unit from the same model same problem have all the power and stuff i need there but still wont work ?

[warey]

good earth?