Urrea UD88 User's Manual And Warranty Information page 79

To check condenser leakage:
- Set the rotary switch to resistance (Ω).
Insert:
- Black lead into COM jack.
- Red lead into VΩRPM CAP jack.
Connect:
- Black test probe to the negative (-) side of the
condenser.
- Red test probe to the positive (+) side of the
condenser.
Watch the bar graph increase. You will see the
resistance increasing from 0 to infinity over a short
period of time.
NOTES:
1. If the condenser is in a conventional ignition system,
make sure the points are open before starting the test.
2. Switch the test leads and check the condenser in both
directions.
3. Make sure to check the condensers under both hot and
cold conditions.
Position Sensors
There are basically two types of position sensors:
Magnetic and Hall-Effect. The magnetic type is simply
a permanent magnet with a coil of wire wrapped
around it.
Hall-Effect sensors usually have three connections:
Power, signal output and Ground. Magnetic sensors
have two wires, one connected to each end of a coil
winding.
Magnetic sensors can be found in some distributors and
consist of a magnetic pickup and a reluctor to change
the magnetic field. In a distributor, the clearance
between the pickup and reluctor on a magnetic
sensor is critical so be sure to check it according to the
manufacturer's specifications. The specifications are
usually between 0.03 and 0.07 inches.
The Hall-Effect sensor uses a small semiconductor
wafer material that has unique characteristics. As
a magnetic field is passed through the sensor it
produces a voltage.
The voltage produced by the Hall-Effect sensor is
proportional to the strength of the Magnetic field
passing through it. This magnetic field may come from
a permanent magnet or an electric current.
Hall-Effect sensors can also be used to measure current
since the magnetic field strength is proportional to an
electric current, which enables the Hall-Effect clamp-
on current probe to measure DC current by converting
the magnetic field into a voltage that can be read by
a DMM.
Hall-Effect position sensors have replaced ignition
points in many distributor type ignition systems. They
are also currently being used to determine the crank
and cam position on distributor-less ignition systems
(DIS), which tells the vehicle's computer when to fire
the coils. This position also tells the computer when to
open the injectors on sequential fuel injected systems.
For checking the Hall-Effect sensor you need to check
the reference voltage coming from the battery at
the connector for the sensor since Hall-Effect sensors
require power where magnetic sensors do not.
5. Magnetic Position Sensor (Pulses) Test
This test checks for the pulses from magnetic
distributor pickup to determine if the reluctor wheel
of the magnetic pickup is damaged.
To check for pulses from magnetic pick up:
- Disconnect the distributor from the ignition module.
- Set the rotary switch to voltage ( V ) and put the
Meter on AC volts.
Connect:
- The test probes to the sensor output leads.
No pulses will appear if the reluctor wheel or the
magnetic pickup is damaged.
NOTES:
1. The clearance between the pickup and reluctor is very
critical. Be sure to check it according to the manufacturer's
specifications.
E N G L I S H
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