Ford C Max 1.8 Zetec (2004) - Audio unit

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Mon 21 Feb 2011 11:57
Ford C Max 1.8 Zetec (2004) - Audio unit - focuson

The settings on my audio unit seem to be lost most times when I get into my C Max. Features like the AVC which is the volume setting to compensatione for engine and raod noise as speed increases. This always reverts to zero meaning that I have to manually increase the volume. I know this is not a major hardship but all the settings revert to zero ro back to the factory settings. It's like the unit loses its memory. The Ford dealer where the car came from tried to fix this under warranty and even replaced the unit with one from another vehicle that they had and it seemed ok for a few weeks but now out of warranty they don't want to know.

The same symptoms with two units suggests to me that the problem may not be with the unit and instead something else linked to it. Is there a memory unit somewhere that may be to blame

As well as the settings being wrong, when I enter my C Max the display on the audio unit is sometimes blank when it should display the current time. I can't wear a watch so I rely on the car's clock alot on the move.

Has anyone any idea what could be wrong and what needs to be done to fix it?

Many thanks

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Mon 21 Feb 2011 12:22
Ford C Max 1.8 Zetec (2004) - Audio unit - Englishbullterrier

Hmm.........most audio units are supplied with a switched +12v from the ignition to turn the radio on and off and a permanent +12v which is for maintaining some memory functions, like those that you spoke of. Maybe it could be an issue with this feed being intermittent o/c ?.......ebt

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Mon 21 Feb 2011 13:25
Ford C Max 1.8 Zetec (2004) - Audio unit - Collos25

Sounds like a car problem and not a radio problem as stated above does it loose the pre programmed stations.One way is to wire a test light up the 12v unswitched supply and see if it stays lit or goes out when you turn off and remove the key you may have to wait some time till the ECU turns off.

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Mon 21 Feb 2011 15:14
Ford C Max 1.8 Zetec (2004) - Audio unit - Chris M

Without putting the key in the ignition, can you turn the radio on? If it comes on, I would take it that there is a working unswitched supply.

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Mon 21 Feb 2011 16:14
Ford C Max 1.8 Zetec (2004) - Audio unit - focuson
Yes the unit comes without the ignition key in
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Mon 21 Feb 2011 16:01
Ford C Max 1.8 Zetec (2004) - Audio unit - Englishbullterrier

Sounds like a car problem and not a radio problem as stated above does it loose the pre programmed stations.One way is to wire a test light up the 12v unswitched supply and see if it stays lit or goes out when you turn off and remove the key you may have to wait some time till the ECU turns off.

Hmm.....some units use non volatile memory for some functions. For instance, my Blaupunkt keeps it station memory even when totally removed from the car. BUT, it's still worth looking at the solid 12v memory feed.........ebt

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Mon 21 Feb 2011 16:18
Ford C Max 1.8 Zetec (2004) - Audio unit - focuson

No it doesn't lose the programmed radio stations - just the various customised settings that you can set like the AVC that compensates for engine and road noise

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Mon 21 Feb 2011 19:59
Ford C Max 1.8 Zetec (2004) - Audio unit - Englishbullterrier

Definately worth checking the 12v memory voltage then........ebt

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Mon 21 Feb 2011 20:42
Ford C Max 1.8 Zetec (2004) - Audio unit - focuson

Thanks

I'll have a look at the weekend

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Mon 21 Feb 2011 22:29
Ford C Max 1.8 Zetec (2004) - Audio unit - Chris M

But ebt, if the radio works without the ignition on, doesn't that prove the 12v constant feed must be working. It's therefore likely to be an internal fault with the radio?

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Mon 21 Feb 2011 22:59
Ford C Max 1.8 Zetec (2004) - Audio unit - Collos25

Thats why you have to wait till the ecu turns off before taking any readings.

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Tue 22 Feb 2011 11:25
Ford C Max 1.8 Zetec (2004) - Audio unit - Englishbullterrier

But ebt, if the radio works without the ignition on, doesn't that prove the 12v constant feed must be working. It's therefore likely to be an internal fault with the radio?

If the radio works with the ignition off, it must still be getting a switched 12v feed to the radio. Do you mean you can switch the radio on without having first placed the key in the lock, or not ?....ebt

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Tue 22 Feb 2011 11:38
Ford C Max 1.8 Zetec (2004) - Audio unit - focuson

Yes EBT

the radio can be switched on without having to put the ignition key in its barrel - but as I mentioned in my first post, sometimes the clock doesn't display the time when I first get in but the main problem is the loss of the settings.

The really puzzling thing is that they are not lost everytime I get in the car - sometimes the settings will be remembered for a few days - other times they will be lost everytime I get in the car so the fault is intermittent

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Tue 22 Feb 2011 12:15
Ford C Max 1.8 Zetec (2004) - Audio unit - Englishbullterrier

And that's why I suspect an intermittent issue with the unswitched 12v t o the memory line, especially as you've tried another unit !

Interested to know the final outcome..............ebt

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