jcb 1CX, Service Manual

Page: 88 / 242

Section C Electrics
9803/8550
Section C
Test Methods 2 - 2 *2 - 2
Issue 2*
Measuring DC Voltage
On the AV0 2003
Move the right slider switch to position A, and the left hand slider switch to the appropriate range.
On an analogue meter
Turn the dial to the appropriate DC Volts range.
Connect the black probe to the nearest available suitable earth point, usually this will be the starter motor earth, the battery
negative, or the chassis.
Connect the red probe to the wire or contact from which you are measuring the voltage.
Measuring Resistance
Make sure there is no power to the part of the circuit you are about to measure.
Connect one probe at one end of the component or wire to be checked and the other probe at the other end. It does not matter
which way round the two probes are placed.
On the AV0 2003
Move the right hand slider switch to position B, and the left hand slider switch to the appropriate Ohms ( ) range.
On an analogue meter
Move the dial to the appropriate Ohms ( ) range.
Measuring Continuity
Make sure there is no power to the part of the circuit you are checking for continuity.
Connect one probe to one end of the component or wire to be checked and the other probe to the other end. It does not
matter which way round the two probes are placed.
On the AV0 2003
Move the right hand slider switch to position B, and the left hand slider switch to position C.
If there is continuity (i.e. very low resistance) between two points the buzzer will sound.
On an analogue meter
Turn the dial to the lowest Ohms ( ) range.
If there is continuity (i.e. very low resistance) between two points the needle will move across fully (or almost fully) to the right
hand side of the scale.
*
www.WorkshopManuals.co.uk
Purchased from www.WorkshopManuals.co.uk