Can any one help me . started car and amp meter jump back and forward light blinking tach was going crazy. Just installed new battery . I have drove car three times sinceand it ran fine .
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First thing I'd check is that the connections on the back of the ammeter are tight - review this article at Panteraplace:
http://www.panteraplace.com/page178.htm
Next, check that your battery is still fully charged, if the ammeter is acting up, then it may not have been passing enough current to the battery, and it's discharging.
As for the tach, what do you mean by 'Crazy'? When my voltage regulator blew, I found that when I revved the engine, too much voltage was being passed through (18+ volts), and my tach. would rise to around 3000, then drop to zero until I shifted, then do the same thing in each gear. If it's anything like this that you're experiencing, test the voltage going to your battery - a simple volt meter that plugs into the cigarette lighter socket will do the trick ...
http://www.panteraplace.com/page178.htm
Next, check that your battery is still fully charged, if the ammeter is acting up, then it may not have been passing enough current to the battery, and it's discharging.
As for the tach, what do you mean by 'Crazy'? When my voltage regulator blew, I found that when I revved the engine, too much voltage was being passed through (18+ volts), and my tach. would rise to around 3000, then drop to zero until I shifted, then do the same thing in each gear. If it's anything like this that you're experiencing, test the voltage going to your battery - a simple volt meter that plugs into the cigarette lighter socket will do the trick ...
After rebuilding my car the tach didn't work so I removed it and sent it out to be repair . since getting it repair when I turn on the ignition switch the tach jumps up to 6000 8000 RPM. I remove tach and sent it back to be repair . they checken it out and said there was no problem with tach . checked all the connections read all the old forms on tach but nothing has help . After car runs for A few minuts every it works fine.
I haven't heard of this problem, but I did find this write up by Bill Taylor recently about the 8920 tach adaptor for MSD 6AL systems ... if you're using an MSD setup, then doing these tests may help to narrow things down.
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You can verify that the 8920 is working in the car using a multimeter. In
the following, +12V DC means the voltage of the battery.
With the engine running the White wire between the 6AL and the 8920 should
read around +2.8 V DC. This indicates that the 6AL is providing a 20% duty
cycle +12 volt square wave to the 8920. This voltage will not change with
the speed of the engine because the signal duty cycle % does not change. If
the White wire reads 0 V DC, you may have a bad connection. If the White
wire reads +12V DC, the 6AL tach output signal is bad.
With the engine running, the Violet wire tach signal out of the 8920
should read as follow:
1,000 RPM ~ 1.27 VAC, 2,000 RPM ~ 2.62 VAC, 4,000 RPM ~ 4.75 VAC
This indicates that the 8920 is putting out the normal point/coil type
signal to trigger the Pantera Tach. Note that we are reading AC voltage here
because we want to see the inductive ringing signal which occurs with each
spark occurrence. The AC voltage reading on the Violet wire increases with
engine speed.
With the engine not running, if you disconnect the White wire from the
8920 (i.e. remove the 6AL tach trigger signal), the Violet wire of the 8920
will read +12V DC. With the White trigger wire then reconnected to the 8920,
the Violet wire will read slightly less than +12V DC. Although the
difference between readings is only on the order of 0.5V DC, this is a
second indication that the 8920 is working correctly.
If you have access to an oscilloscope, the 8920 Violet wire ringing signal
is around 8,300 cycles and has a voltage peak of around +20 volts. Since the
8920 has been used on many Panteras, the +20 volt peak and the 8,300 cycles
is adequate for the Veglia tach.
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--------------------------------------------------------------------------
You can verify that the 8920 is working in the car using a multimeter. In
the following, +12V DC means the voltage of the battery.
With the engine running the White wire between the 6AL and the 8920 should
read around +2.8 V DC. This indicates that the 6AL is providing a 20% duty
cycle +12 volt square wave to the 8920. This voltage will not change with
the speed of the engine because the signal duty cycle % does not change. If
the White wire reads 0 V DC, you may have a bad connection. If the White
wire reads +12V DC, the 6AL tach output signal is bad.
With the engine running, the Violet wire tach signal out of the 8920
should read as follow:
1,000 RPM ~ 1.27 VAC, 2,000 RPM ~ 2.62 VAC, 4,000 RPM ~ 4.75 VAC
This indicates that the 8920 is putting out the normal point/coil type
signal to trigger the Pantera Tach. Note that we are reading AC voltage here
because we want to see the inductive ringing signal which occurs with each
spark occurrence. The AC voltage reading on the Violet wire increases with
engine speed.
With the engine not running, if you disconnect the White wire from the
8920 (i.e. remove the 6AL tach trigger signal), the Violet wire of the 8920
will read +12V DC. With the White trigger wire then reconnected to the 8920,
the Violet wire will read slightly less than +12V DC. Although the
difference between readings is only on the order of 0.5V DC, this is a
second indication that the 8920 is working correctly.
If you have access to an oscilloscope, the 8920 Violet wire ringing signal
is around 8,300 cycles and has a voltage peak of around +20 volts. Since the
8920 has been used on many Panteras, the +20 volt peak and the 8,300 cycles
is adequate for the Veglia tach.
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Still having problem with tach but only when I first start up car. After doing some work I found a fuse that reset it's self under the dash this 30 amp fuse is hooked into the turn single. There must be one hell of a short in the blinker switch . After disconecting all my problems stopped but now I have no blinker .The blinker switch looks like a big mess with wires sodered in to it . I think I have a mallory uni-light distrubuter with a mallory coil .
quote:The blinker switch looks like a big mess with wires soldered in to it .
Bill Taylor can most likely fix that for you, for a flat fee of $50.
Contact him at:
SOBill@aol.com
Larry