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Discussion Starter #1
Ok,
I was having an issue with #7 blowing. after determining the proper size fuse 10A (PO had 5) it still was blowing. No gauges were working, I lived with it, checking my oil and gas regurlary. Then after a couple of weeks, the battery went dead. Alternator was only putting out 12.2 volts.

today i determined the blown fuse was due to an issue with either the heater fan or fan switch. disconnected switch, replaced fuse and gauges stay on.

now it appears that my alternator is putting out 13.8 V.

thoughts?

Rande
 

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But Mad North-Northwest
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Well, the voltage regulator at the alternator senses system voltage through the alternator warning light on the dash. If the light loses power it could probably cause low voltage at the alternator.

The wiring diagram shows the warning light pulling power from fuse 8, but this could be an error. God knows I've found enough other mistakes in there...
 

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do you recall if fuse #7 was blowing even with the heater fan switch turned off?
Did you hear the fan blowing away happily?

The fan could be seizing (quite common!), that would draw excessive power.
 

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Discussion Starter #4
Tom, the battery light would come on with #7 blown, so that is correct.

SpiderSeries 4, uncertain if the blower motor was working. the only saving grace is that I live in Florida, so i really don't need the heater/defogger at least until December. Is removing the blower motor a difficult job? it looks as if it takes removing most of the lower part of the dash assembly.

Thanks Guys
Rande
 

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yes, removing blower motor is one of those real PITA jobs! But, you can try putting 12v straight to the blower motor and see if it runs well, look just above your gas pedal, you will see the wiring connections there on the heater assy. itself.
dont know which ones you need to connect to though.......experiment a bit!
http://www.alfabb.com/bb/forums/348135-post6.html
 

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Discussion Starter #6
Thanks Dom, that will be a big help.
Rande
 

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the first day I had my 85 i had a similar issue after buying every 10a bullet fuse available in my small town i went to work.. Similar to you i was chasing everything i could find in the factory wiring diagram connected to fuse 7 . I had determined it HAD to be the ignition switch as with everything under the dash disconnected it would blow as soon as i hit the key to "run". and was about to start pulling parts and drilling out the security ricvit on the switch when papajam told me to disconnect the pinkish wire to the cigarette lighter tape it off and try again ...problem solved He said it was a common problem at the time with spiders so just a thought also if you have not already.... contact Papajam via pm and politely request one of his suitable for framing wiring diagrams it is worth its weight in gold
 

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contact Papajam via pm and politely request one of his suitable for framing wiring diagrams it is worth its weight in gold
I don't think Jim (Papajam) has gotten round to a coloured S4 wiring diagram (yet:)).....he has the alfa b/w one on pdf which is very useful, though, but nothing like his own coloured transcriptions..........I'd even pay to have one of those for an S4!
 

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Discussion Starter #10
Hi Guys,
i did disconnect the cigar lighter, it is the heater issue.

I may be crazy,( i own an alfa, 'nuff said) but the car seems to be running better in several ways. not certain, but i think the voltage regulation and fuse #7 is really so connected, that the heater problem was doing something even before the fuse blew.

R
 

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Did you manage to get the heater fan to turn with direct power?

I would in any case drop down the fuse box, turn it over and thoroughly check and clean with contact spray all the wiring connections there.
 

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Discussion Starter #12
Hi Dom,
haven't had a chance, will keep updated.
thanks
R
 
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