Pioneer MVH-350BT fitting problems

I've read some posts about fitting aftermarket headunits & have another question.

I've bought the above unit & the radio won't switch off with the ignition, i've read about swapping A4 & A7 which i've done but no joy.

Both A4 & A7 on the connector appear to be permanent 12V supplies & none of the 2 disappear when the ignition is switched off

Any clues?

Both A4 & A7 on the connector appear to be permanent 12V supplies & none of the 2 disappear when the ignition is switched off

Well, its not quite controlled by the ignition switch, but rather the BSI so there is some computer control involved. You may find it takes a few seconds for the BSI to switch off its controlled voltage. Its definitely pin 4 and pin 7 of the ISO power plug that need to have their positions reversed on the plug on the early shape and the facelift shape, but I don't know if it still holds true with the new shape car.

Which year and shape car do you have?

Arfur Dent wrote:

Both A4 & A7 on the connector appear to be permanent 12V supplies & none of the 2 disappear when the ignition is switched off

Well, its not quite controlled by the ignition switch, but rather the BSI so there is some computer control involved. You may find it takes a few seconds for the BSI to switch off its controlled voltage. Its definitely pin 4 and pin 7 of the ISO power plug that need to have their positions reversed on the plug on the early shape and the facelift shape, but I don't know if it still holds true with the new shape car.

Which year and shape car do you have?

Cheers for the reply, it's a 2003 53 plate. Not sure about the shape but it's a 1.4 petrol if that helps.

it's a 2003 53 plate

Its an early shape, like the red one at the top of the screen. Maybe someone has already modified the wiring in the car?

I can see the pioneer doesn't have an iso shape socket on the back, I don't know if this is adding to the confusion.

But a 2003 car will need 4 and 7 swapping over so the computer can put the car to sleep and allow the memory to stay backed up.

One of the pair (4 and 7) will be live all the time, and the other will switch to 0v after a while after switching off the ignition, you may even have to remove the key or open the drivers door, I can't remember, but its worth trying all those (even exit the car and lock it - view the voltmeter through the window). Its because its under computer control and its the computer that decides when to switch the radio off.

A bit of an update,

I just checked my car (early shape), standard head unit and I can press the power button after removing the key from the ignition, open the drivers door and even lock the car and the radio stays powered up.

So your 12v on each power line (4 and 7) seems good. The computer will switch the radio off when its good and ready.

I will investigate further tomorrow to see how long the stereo stays powered up for. I hope this helps!

Arfur Dent wrote:A bit of an update,

I just checked my car (early shape), standard head unit and I can press the power button after removing the key from the ignition, open the drivers door and even lock the car and the radio stays powered up.

So your 12v on each power line (4 and 7) seems good. The computer will switch the radio off when its good and ready.

I will investigate further tomorrow to see how long the stereo stays powered up for. I hope this helps!

Cheers, i was starting to panic about dead batteries in the morning etc.

I checked this morning & when i open the door the radio comes on.