After market Radio not powering down

Audio, ICE, Speakers, Head Unit, CD, CD Multi changer. If you have a question about any Citroen C3 related Audio, then this is the place.

Please indicate if there is a Citroen CD multi-changer, drawer or cubby under the CD/Radio, if there is the Navigation unit, CD or Radio options.
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Only post questions about AUDIO equipment in this topic please. In car entertainment, ICE, Android Auto, stereo and sat-nav are all welcome here
My Name: rustyh6281

Posts: 1
Joined: Fri Dec 02, 2011 7:55 am


Hello ...

I have just fitted an after market CD / MP3 player to my girlfriends car...
It wasn't a real problem, as the cables fitted quickly...

BUT ...
1) Can i assume i can not get the attachments the wrong way around? Looking at a previous post one set is for the speakers
2) The radio continues to draw power when the ignition is off. The car had a low battery this morning because it kept the radio powered all night!?

How can i deal with this? I just changed over the cables .. i thought that should be enough?

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My Name: C3driver52

Posts: 2012
Joined: Sat Apr 30, 2011 7:40 pm
Model: C3 2002-2005, Original shape model
Year: 2003 (03)
Engine Size: 1.4 i
Fuel Type: Petrol
Mileage: 79984
Trim Level: VTR+
Gearbox: Manual 5 speed
Engine name: TU3 (75 PS)
Has thanked: 146 times
Been thanked: 78 times


Welcome to the C3 forum rustyh6281.

You are right, the two plugs are different, one is for the speakers and the other for power/control. You can't get that bit wrong.

The problem with the C3 (as you have found out) is that the constant power to keep the memory in the radio and the power to shut down the radio when the 'ignition' is off are wrong (as in not meeting the ISO spec) and not compatible with an aftermarket radio.

The problem is:
Pin 4 and Pin 7 in the power plug (socket on the back of the radio) are reversed.

there is a forum post about pin 4 and pin 7 reversed on the ISO connector for the Citroen C3

Pin4 should be permanent live with 12v for an aftermarket radio, but its switched by the computer on the C3 and pin7 should be switched on with the 'ignition' or accessories switch position for an aftermarket radio, but its a permanent 12v on the C3.

This causes the radio to stay on when it should go off.

The solution is:
To swap pin4 and pin7 over, either in the plug or by cutting the cables and re-joining them or finding an adaptor that switches the two cables over.

The adaptor will be the best solution as its easily reverted in case of fitting the original radio back. I will find which adaptor will work.
My Name: omarsmith

Posts: 23
Joined: Tue Feb 28, 2012 12:42 am
Model: C3 2002-2005, Original shape model
Year: 2002 (02)
Engine Size: 1.4 i
Fuel Type: Petrol
Mileage: 134000
Trim Level: Touch
Gearbox: Manual 5 speed
Been thanked: 1 time


Hi there rustyh6281 - just to complete citroenowner52's advice, suitable adapters currently available can be found on eBay here (UK site) and are inexpensive at between £5-15 - however, when choosing one to buy, it is recommended that you:
  • Buy an adapter specifically designed for a Citroen C3, rather than a generic adapter listed for many models of Citroen (I can't vouch as to whether the swapped pin 4/7 issue is the same on other models)
  • Look to see if the item specifically states that pins 4 and 7 are switched to fix the power down issue
  • Contact the trader on eBay before buying to check if the adapter will work problem-free on the C3.
Sorry this info has only caught up to you at this point - hope it's still useful to you or other C3 owners fitting aftermarket stereos!
My Name: Missing Lincs

Posts: 844
Joined: Mon Mar 05, 2012 9:29 pm
Model: C3 2002-2005, Original shape model
Year: 2004 (04)
Engine Size: 1.1
Fuel Type: Petrol
Trim Level: Desire
Gearbox: Manual 5 speed
Engine name: TU3 (75 PS)
Location: United Kingdom
Has thanked: 46 times
Been thanked: 35 times


If you had audio controls on the steering stalk and/or a trip computer you will find that these also don't work, certainly the case on C3 Mk I models. You can get an adaptor which fixes these issues as well as the power problem.
If at first you don't succeed, destroy all the evidence and pretend you never tried :lol:
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