Climate - factory defaulting at random

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Mon 14 Aug 2006 18:29
Climate - factory defaulting at random - J1mbo
Hi, the CC on my Mazda 6 will at random default to its factory settings when the car is started. The dealer has changed the CC module but they are now a little puzzled as its happened again.

Has anyone had this on a Mazda or maybe another brand of car? The car is less than a year old.

Ta for any suggestions.

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Mon 14 Aug 2006 20:17
Climate - factory defaulting at random - Aprilia
Sounds like loss of backup memory power when the car is started rather than a problem with the ECU itself.
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Mon 14 Aug 2006 20:34
Climate - factory defaulting at random - J1mbo
It was'nt the ECU, but the Climate Control Module that was changed. The stereo has'nt been affected.
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Mon 14 Aug 2006 22:20
Climate - factory defaulting at random - kithmo
Does it do it every time you start the car ?
Just a shot in the dark here, but I'm thinking voltage surge from the alternator. Try starting the car with the headlamps and heated rear screen switched on and see if it still does it. If it doesn't, then have the alternator output checked.
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Mon 14 Aug 2006 23:32
Climate - factory defaulting at random - J1mbo
Hi, its very intermittant. Might be ok for a week , then it will do it, then maybe again the next day or it might be ok for a couple of weeks. You get the idea......

Not sure if its happening after the ign is on, or after cranking the engine.
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Tue 15 Aug 2006 01:12
Climate - factory defaulting at random - Aprilia
It was'nt the ECU, but the Climate Control Module that was
changed. The stereo has'nt been affected.


Yes, I mean the CC ECU (ECU=electronic control unit - doesn't have to be engine control) - what you've called the CC Module.
The stereo doesn't come into the argument.
I think you have voltage 'brownout' when the car is started, causing settings to be lost from memory.
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Tue 15 Aug 2006 13:40
Climate - factory defaulting at random - J1mbo
But I would expect the radio to lose its memorys if this was the case.
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Tue 15 Aug 2006 15:47
Climate - factory defaulting at random - Altea Ego
Not always.

Brownout was mentioned, not voltage loss.A brownout is where voltage falls, but not actually cuts out. Some devices have better tolerance than others to brownouts. The settings on a radio use minuscule amounts of power to keep them, the CC unit probably more greedy and less tolerant than the radio.
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TourVanMan TM < Ex RF >
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Tue 15 Aug 2006 16:42
Climate - factory defaulting at random - kithmo
If it's intermittent, I'd be looking at the connector, the KAM (Keep Alive Memory) feed in particular (if you have a wiring diagram).
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