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Battery drain in Mk 2 Focus – radio advice required

Max Thunder

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I own a Mk 2, 2010 Focus and have had an issue where the red LED light around the central power button/volume control of the radio (a 6000cd standard model) has been staying lit once the vehicle has been locked etc. The instrument cluster has been going to sleep as normal so only the radio seems to be a problem. The vehicle battery has been dead next morning on a number of occasions and required a jump start. battery was replaced and alternator tested (normal) for elimination purposes. An auto electrician ran some tests inc testing for battery drain but on that particular day the radio was 'behaving' and he couldn't find a problem.

The dead battery occasions became more frequent until I removed the fuse for the radio unit (nothing else was done) several weeks ago and this solved the problem. The car has started first time every time since, including an occasion where it had sat unused for 6 days, so it seems clear to me the radio not entering sleep mode was the problem.

My main question is this: do you think a replacement radio unit will solve the problem, or could the issue be a defective/faulty wire behind the console somewhere? I asked a knowledgeable car-minded friend and they also suggested it may be down to a problem with the fuse box. 

My wife is getting fed up having no radio or cd player for longer journeys so I would like to try and sort this!

'JW1982' offered the following advice in the topic 'Parasitic drain?' on this site originally from 31 March 2014:

"The radio is basically a stand alone CANbus module. Even if the radio is switched off it still has a 12 Volt power supply. There is no other module which switches off the power supply of the radio.

The radio communicates with some of the other modules over the CANbus network. After locking the car all of the modules should stop to communicate. If there is no communication the CANbus network should enter sleep mode after a certain time.

In your case the radio prevents the CANbus system from entering sleep mode. I have seen before that a defective radio still tries to communicate or puts a small voltage on the CANbus network which can be recognised as communication. This results in the fact that the CANbus system stays active which can drain the battery in a relative short time.

My experience is that replacing the radio solves the problem"

Does anyone have reason to think simply replacing the radio would not solve the issue?

Many thanks.

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2 hours ago, Max Thunder said:

My wife is getting fed up having no radio or cd player for longer journeys so I would like to try and sort this!

Well you could fit a switch as a measure to allow the radio to be used.

More seriously while  than it is more probable than not that replacing the radio would work it is difficult to be certain.

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