Making headunit work without engine running

gavin18787

Junior Member
Hi just after a little advise really as ive just fitted my new headunit as i wanted one I could use with an Ipod. Its a pioneer P4900IB. Its all running fine and dandy but dosent work unless i have the engine running //content.invisioncic.com/y282845/emoticons/frown.gif.a3531fa0534503350665a1e957861287.gif

I got round this problem with my old headunit (a JVC) by changing the position of the fuse on the back of the unit. However this unit only has one position for the fuse to go into.

I have also tried swapping the yellow and red wires over as show in the pic but this has not helped either.

audio_002_medium.jpg


Any help would be very much apriciated //content.invisioncic.com/y282845/emoticons/biggrin.gif.d71a5d36fcbab170f2364c9f2e3946cb.gif

Gavin

 
My guess is whatever you tapped into for your remote wire isn't live when the ignition's on, but only when the car is running. Search for a different remote wire.

If it's the same as before, and worked before, ****ed if i know

 
Here is the deal,

The yellow wire should have power all the time, directly from the battery if possible (I don't really bother, I just use the stock wiring)

The red wire should have power any time the key is not in the OFF position, which includes the accessory position where the electrical system is on without the engine running. btw: I'm talking about the red wire labeled acc

so use a multimeter to find a wire that has power when the keys are on acc or when the engine is running and it'll fix your problem

 
Ah cheers for all the help //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

Previously it wasnt ideal as the headunit was always on and you had to manuely switch it off.

I will try and find which wire goes live when the key is in the acessory position, however i have a feeling none of them do as my last corsa didnt have this problem and the ISO just connected straight up and it all worked. May have to go for the permanent live thingy again

 
Right ive been having a fiddle today and am still none the wiser //content.invisioncic.com/y282845/emoticons/frown.gif.a3531fa0534503350665a1e957861287.gif

Connected up all of the remote wires as suggested and im still not getting anything unless the ignition is fully one.

Also out of interest I joined the yellow and red wires to see if i could get it constantly live and manually switch it on and off on the headunit (not ideal i know but better) This worked but when ever the headunit was on so were all the dash lights and fan etc so thats not any good either //content.invisioncic.com/y282845/emoticons/confused.gif.e820e0216602db4765798ac39d28caa9.gif

So im now thinking it is the accesory position on the ignition that is faulty. What is the best way to test it?

Cheers for all the help so far //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

Gavin

 
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