| Author |
Message |
David Feinberg (Fastradio2)
New member
Username: Fastradio2
Post Number: 40
Registered: 4-2002
| | Posted on Saturday, June 08, 2002 - 9:40 pm: | |
Hi Pauli,
Although Ferrari do follow Ohm's Law (normal electrical formulas), a more meaningful test is in order to get a baseline of the actual current draw with the engine off. Here's how I would/have approched this problem in the past.
With all accessories off in the car, including an/all aftermarket electical devices...Disconnect either battery terminal and connect in series a mutimeter capable of reading current. Starting on the 5-10 amp scale, keep turning the range of the ammeter down until you know precisely what the residual current draw is. On a vehicle of this vintage, one would expect to see less than 100ma draw, with 50ma or less, being ideal. If that's what you have, the problem lies with the battery or alternator.
However, if the draw is higher than that (50-100ma)...Leave the ammeter in place and start removing the fuses, one by one...and watch for the draw to drop. If, after removing all the fuses, you do not see the draw drop, do the same for the relays...
Eventually, you'll isolate the circuit that is causing the draw. The most common items I've seen to cause excessive current draw are the hood and trunk lights not turning off when the lids are closed. Radar detectors, if not switched off with the ignition switch (particularly the Valentine One) draw considerable standby current. Ditto for the older cell phone units...
Hope this info gives you a better starting point.
Regards,
David |
TomD (Tifosi)
Member
Username: Tifosi
Post Number: 785
Registered: 9-2001
| | Posted on Saturday, June 08, 2002 - 8:16 pm: | |
is the alt working? |
Pauli Salmu (Psalmu)
New member
Username: Psalmu
Post Number: 37
Registered: 10-2001
| | Posted on Saturday, June 08, 2002 - 4:25 pm: | |
It hasn't had any major electrical problems but now the battery has been drained twice. The first time I thought that sometimes it just happens and I recharged the battery but now it's dead again after a few days. I checked the resistance between the terminal cables when they were disconnected from the battery and nothing was turned on and it read about 3 Ohms which means (if normal electric formulas hold even in a Ferrari) 4 Amp current with battery connected: that should indeed work well to drain it fairly quickly. Any ideas where to start looking for this gremlin? |
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