Hey all. Having an electrical issue. The missus got a 2004 focus 1.4 liter. It had an ancient nokia car kit in it with the standard header unit. Today we put in her after market unit and was working great. Got home and decided to remove all the old car coms kit, whoever installed it took a feed from the ignition 12v wire the constant 12v wire and the ground. We removed the wires and now the radio wont turn on. I used a multi meter and I have 12v across the 3 wires that were tapped into so they are not severed. What am i missing? All fuses are ok, No other wires were tapped into for this old coms kit so really not sure why It wont turn on . the stock head unit doesnt even work so def messed something up. Any ideas?

Now, when you say you have checked the fuses, on most head units there is a built in fuse usually located at the rear of the unit, in addition to 'inline' fuses. I suppose you've checked this?

7 hours ago, StephenFord said:

Now, when you say you have checked the fuses, on most head units there is a built in fuse usually located at the rear of the unit, in addition to 'inline' fuses. I suppose you've checked this?

Hey Stephen, Yes I checked the rear fuse. I used a multi meter on sound mode to check. I also checked the fuse that lives behind the glove box, Have tried the radio in another car and it works so its def the car

Still no luck with this. Anyone got any ideas?

Voltage only shows half the story.  If the wires have been partially cut you might not be getting enough amps through now.

Also worth checking you've definitely got live and switched live in the right places.  As well as a good earth.

On 3/30/2019 at 11:44 PM, andyc5110 said:

I used a multi meter and I have 12v across the 3 wires that were tapped into so they are not severed.

You have to be a bit careful with multimeter readings. On open circuit or very bad connection lines the meter can still give a good reading, as it draws very little current (typ 10M ohm input resistance). So like Tom says, the power may not be getting through. You need to test the circuits, including ground, with the radio connected and on, so it is drawing current. This may be easier said than done, but sharp pins can help, by penetrating the wire insulation.