Aftermarket Stereo interfering with lights mk2.5 focus

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Hi guys/gals

i am new to this site and joined as a last ditch effort to find the problem i basically have a 2010 plate ford focus owned it for 2 year nearly, no problems at all except for the stereo i replaced it with a pioneer and found my side lights once on wouldn't switch off unless i take the fascia off of the stereo or switch the engine off so i bought a kenwood thinking it would resolve the issue but it hasn't i haven't bought a can bus adaptor to go with the after market stereo for the stalk on the steering wheel as yet but i visited my local halfrauds store and spoke to there sound engineer today he reckoned the fault has to be in the cars ecu because if i plug the original cd6000 back in the issue go's away, the aftermarket stereo works fine without a canbus adaptor but its effecting my lights also i just bought a brand new light switch for the dimmer and the dimmer wont work properly (it flickers if set low) with the after market stereos in but will with the original stereo its fine im literally pulling my hair out at the moment just wondering if any one has experienced this issue or similar or even if not having a canbus adaptor could cause this issue any help would be grateful.

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I removed the ISO block completely from my focus mk2.5 when fitting an aftermarket headunit to save space at the rear because I've fitted alot of RCA cables 15 in total for two amps, tv tuner, reverse camera, PlayStation and a 10" screen,

I can tell you that none of the cables leed directly to the parking lights, The interior light feed is linked to the headunit via "The Gem unit"

The GEM general electric management unit is the Can-Bus brain it controls lights and locks and is seperate to the ECU 



I used a Haynes manual for reference, 


But I've never experienced anything like your describing man.







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holy moley that looks like a lot of work i'm hoping i don't have to cut through any wires as i'm not experienced with car electrics as such, give me a spanner/socket set and a part to replace i will get the job done but give me a meter tester or what ever they are called and i will look at you stupidly and you would laugh lol the stereo works fine (single Din) with the adaptor on, it just doesn't have the canbus adaptor on i'm wondering if that could be the issue as i cant see it being an ecu issue or if any one else has had this issue and been able to resolve it (hopefully without cutting wires) lol. seems the page didn't load correctly for me and i didn't read the full comments so if i haven't misread it could be because i need a can bus adaptor on the stereo ? and it hasn't got anything to do with the ecu ?


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OK An update for any one using an aftermarket radio and when your engines on even if you turn your lights off the side lights stay on I got to the bottom of it its the Can Bus i spoke to a guy from down south (i'm from Yorkshire) at dynamic sounds explained the situation and he said it just may be the Can Bus as i had no steering wheel stalk adaptor so i spent the £38.99 and bought one and to my surprised it worked turns out the can bus was sending power to my stalk on the steering wheel and because it had no where to go was feeding back into the cars electrical system don't know if its designed like that or its a error but the stalk adaptor removed the error and now i have use of my stalk again, win win in my eyes.

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