Where does the tachometer get its signal?
On recent EMS found on modern vehicles, the signal for the tachometer is usually generated from an ECU which derives the information from either the crankshaft or camshaft speed sensor.
What would cause a tachometer to stop working?
A blown fuse is a potential problem with the tachometer. Check the fuses to ensure they are properly functioning. Bad wiring can also be the cause of a malfunctioning tachometer. If you have a digital display, the LED lights may go out on the tachometer, or may not display correctly.
How do you check alternator rpm?
Start the vehicle and wait for it to idle down to normal idle speed. At this point the meter should be displaying a fairly constant AC voltage. If this is the case, rev the motor up and down and observe the reading on the meter. The AC voltage should rise when the engine RPM’s rise and fall when the engine RPM’s fall.
How does a diesel engine tachometer work?
Electronic tachometers work by counting pulses generated by the ignition system, alternator, tach signal generator, or magnetic pickup sender. The tach is hooked up to +12VDC, Ground, and one of the signal sources listed above. From this information, the tach displays the correct engine speed.
Is there a fuse for the tachometer?
Check the Fuses: If you look for the fuse box in your car, find the fuse for the tachometer. If it has blown this could be the source of your problem. A blown fuse may be discoloured and could have a break in the metal strip.
Can I use an AutoMeter tach wire with a VDO alternator?
Not shure if this works with your AutoMeter tach, but it works real well with Vdo tachs. http://www.egauges.com has online instructions for many brands of gauges. [/URL]attach the tach wire (s) to something inside the alternator, is this also possible on the Ford alternators??
How many different types of alternator Tachometers are there?
I have since discovered that there are two styles of alternator-pick-up tachometers. The one on the wife’s truck, a VDO, actually has a wire that taps INSIDE the alternator on one of the three terminals.
Is it possible to add a tach wire to the alternator?
Thanks. [/URL]attach the tach wire (s) to something inside the alternator, is this also possible on the Ford alternators?? Yes its possible with a ford alternator. It is called an AC tap. You have to attach a lead off one of the stator poles usually at the rectifier.
Does a 3G alternator have a seam in the cord?
This unit has a two-wire cord that terminates in a sensor-gizmo that “straddles” the seam between the two halves of my 1985-model alternator. From what I see, the large-case 3G alternators lack this “seam”.