Electrical problem

M0T

M0T

M0T

Soldato
Joined
23 Aug 2003
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Now I was hoping to have another car long before now but finances haven't panned out as I had hoped, so I am still driving my Alfa shed.

I discovered today that when I turn my main beams on my radio resets itself, any ideas what would cause something like that?
 
The positive feed or the earth to the radio is being interrupted when you turn the lights on, it sounds like. I assume the radio comes back on again.
So the current surge or 'inrush' of the lights coming on is 'stealing' the radio's power momentarily.
I'd suggest the lights' power supply or, more likely, earth, is dodgy somewhere so it's coming through the nearest circuit ie the radio. It depends how the lights are wired, really.
Check all the earths to the fusebox(es) and elsewhere.
Disconnect each headlight to see if it's one or another that's causing this, or both together.
Check the radio's earth.
And so on!
 
Doesn't seem to be any problems with any of them - could a shafted battery be causing the issue?
 
I was having problems starting the car a few weeks back, battery voltage read 12.2v and would drop to 9.8v on cranking.

I checked through the inspection holes and the water was lower than it should be and there was a fair amount of sulfation. I took the battery out and topped up the water and then charged it up.

Just checked the voltage now and it was reading 12v (11.7v with all the electrics running before cranking) but the car still turns over without any issues.

Car is a Halfords Calcium tech heavy duty thing - think it is 4.5 years old.
 
You need to do some further tests on that battery..
Drop test it from a fully charged condition and note the volt drop / hold
http://www.aa1car.com/library/voltage_drop_testing.htm

Then check the charging circuit as well, make sure the alternator isn't over or undercharging it or your new battery (if you need one) wont last long.

My first reaction to the OP was Alfa = bad earth because it's rotted away :D
 
Apparently lots of Alfa electrical gremlins can be put down to a non-perfect battery... I'd definitely check the earth of course, but it's worth checking the battery.

The battery voltage should really be 13V+ with the engine running...
 
Right I have changed the battery and cleaned the earths, problem was still happening with the added issue that the car was randomly not starting :confused:

Anyone want to set it on fire for me?

Edit: Battery is 13.4 with engine running.
 
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