Heated rear window/switch flashing

pepper&boulou

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Hi guys my heated rear window switch warning light has started flashing as opposed been constant when turned on. Never noticed it doing that before is that normal or am I just paranoid. I've just had a thought my lecky aerial comitted suicide during the icy weather, motor would not switch off so I disconected the earth as it was doing my head in .it was annoying any way, I never listen to the radio just the cd so it going up when not needed is not much loss , but anyway do you think disconnecting the earth has caused the above. :confused: :eek: :confused:
 

Steve_Perry

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pepper&boulou said:
Hi guys my heated rear window switch warning light has started flashing as opposed been constant when turned on. Never noticed it doing that before is that normal or am I just paranoid. I've just had a thought my lecky aerial comitted suicide during the icy weather, motor would not switch off so I disconected the earth as it was doing my head in .it was annoying any way, I never listen to the radio just the cd so it going up when not needed is not much loss , but anyway do you think disconnecting the earth has caused the above. :confused: :eek: :confused:
If your rear demsiter switch starts flashing it means your battery can't deliver enough juice for the demister to work. Could be a sign that your battery is on its way out. Is it flashing only if the car is idle? or does it flash if you're driving down the road too (i.e. with the engine revving). Either way nothing to panic about, just a sign of a weak battery. Also when you say you disconnected the earth, I presume you mean for the aerial only.

S.
 
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pepper&boulou

pepper&boulou

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Steve_Perry said:
If your rear demsiter switch starts flashing it means your battery can't deliver enough juice for the demister to work. Could be a sign that your battery is on its way out. Is it flashing only if the car is idle? or does it flash if you're driving down the road too (i.e. with the engine revving). Either way nothing to panic about, just a sign of a weak battery. Also when you say you disconnected the earth, I presume you mean for the aerial only.

S.
steve
Bought new battery 8 months (heavy duty) ago switch flashes all the time regardless of engine speed ,thought the wire was only connected to the aerial will reconect it see if makes any difference .Do yo think alternator is on its way out, car starts first time, lights not dim, checked fuses, look ok!
 

Steve_Perry

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pepper&boulou said:
steve
Bought new battery 8 months (heavy duty) ago switch flashes all the time regardless of engine speed ,thought the wire was only connected to the aerial will reconect it see if makes any difference .Do yo think alternator is on its way out, car starts first time, lights not dim, checked fuses, look ok!
Hmm, strange, in that case the easiest test is to reconnect that earth then and see if all becomes normal again. It could be a shared earth I suppose.

Otherwise I am at a loss. Sorry mate.

S.
 
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pepper&boulou

pepper&boulou

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Steve_Perry said:
Hmm, strange, in that case the easiest test is to reconnect that earth then and see if all becomes normal again. It could be a shared earth I suppose.

Otherwise I am at a loss. Sorry mate.

S.
Cheers anyway Steve, they say two heads better than one. ;)
 

NormanB

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pepper&boulou said:
Cheers anyway Steve, they say two heads better than one. ;)

In theory - yes, but a greater probability of head gasket failure ;(

NormanB
 

sym

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LOL !

P.S. this is electronics forum material . . but I can't move it :(

S.

moved it for ya! -Shude
 
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pepper&boulou

pepper&boulou

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NormanB said:
In theory - yes, but a greater probability of head gasket failure ;(

NormanB
How do you come to the conclution that faulty rear demister is caused by head gasket failure? :eek: :eek: :eek:
 

Steve_Perry

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pepper&boulou said:
How do you come to the conclution that faulty rear demister is caused by head gasket failure? :eek: :eek: :eek:
It was a joke to your two heads comment. :D

S.
 
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pepper&boulou

pepper&boulou

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Steve_Perry said:
It was a joke to your two heads comment. :D

S.
Thank god for that I NEARLY HAD KITTENS :eek: :eek: :eek:
 

jimmy

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Yes, definetly a low voltage problem. Had it on mine and replaced the battery. For some reason my car had a low capacity battery for the spec so I fitted a really big one and now have no problems.

It is designed that way so as not to discharge the battery even more, if the battery voltage drops to below 10 or 10.5 volts (I think) then you start to get all sorts of problems with ECU, ABS etc.
 

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If it's very cold, ie the glow plugs are working their nuts off, and I put the heated seats on straight after starting the engine they tend to flash for about 5secs. Looked it up in the handbook and as said above it points to low voltage.
 
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pepper&boulou

pepper&boulou

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marcos said:
If it's very cold, ie the glow plugs are working their nuts off, and I put the heated seats on straight after starting the engine they tend to flash for about 5secs. Looked it up in the handbook and as said above it points to low voltage.
must get battery checked ,as I said its less than 8 months old. :mad:
 
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pepper&boulou

pepper&boulou

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:confused
pepper&boulou said:
must get battery checked ,as I said its less than 8 months old. :mad:
Had the battery checked its A ok putting out nearly 14 volts , reconnected aerial earth made no difference so just disconected power wire to aerial kept earth on. its back to the drawing board guys. :confused: :confused: :confused:
 

Thmsshaun

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Hmm. I know Im dragging up an old thread here but did you ever get the problem sorted. I have had this with my 202 and thought it was the switch. I got a replacement and found it didnt help.

Then on removing rear trim panels and parcel shelf to fit some new speaker I noticed some corrosion on the terminals to the rear window. Give these a clean and job done. No more problems.

Hope it helps if not usefull for other people.
 

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