Tracing Circuits; To Check Continuity - Triumph 2012 Tiger 800 Service Manual

General Information

Tracing Circuits

The following is a description of two types of
common electrical failures, and some of the
methods which may be used to find them.
Open circuit
A break in an electrical circuit - current cannot flow.
Usually caused by a break in a wire or
connection. Open circuits can often by intermittent,
making diagnosis difficult.
Short circuit
A 'short cut' in an electrical circuit - current by-passes the
intended circuit, either to earth or to another, different
circuit. Often caused by failure of the cable insulation due
to chafing or trapping of the wire. There are two different
types of short circuit - short to g round and short to Vbatt.
A short to ground means that the current is going to earth
before it reaches the component it is supposed to feed.
These are often caused by chafing of the harness to the
frame or wires trapped between a bolted component, and
will often blow the fuse on that circuit.
A short to Vbatt is a short to battery voltage ( 1 2 Volts)
and is caused by a live power supply wire contacting an
adjacent cable. Note that it is also possible for a
sensor reference voltage to short to an adjacent circuit,
which can also cause electrica l failures and DTCs
<Diagnostic Trouble Code) to be stored.
When tracing a wire that is suspect, carefully check the
circuit diagram before starting. Remember:
•
a wire may d iverge at a splice and go off to
feed other circu its.
working, check for wiring fau lts from the
splice onwards.
•
the circuit diagra m is not an accurate g u ide
to the actua l location of the parts when fitted
on the bike. lt is a schematic d iagram of the
circuits.
particularly where engine management items
are concerned, the circuit is only completed
by the ECM. If the ECM is not con nected, the
circuit may reg ister as open.
1.1 6
B reak
l_
cablec or by a loose
5
Volt
If these circuits a re
Manual
SeNice Tiger
-

To Check Continuity:

Ensure the circuit being tested is switched off before
measuring continuity. Damage to the Digital Multi
Meter <DM M> may result from testing a 'live' circuit with
the meter set to resistance (Q).
In the example below, the ground circuit continuity is
being tested from the battery to the frame.
Continuity <resistance) Check
•
locate each end of the wire .
•
Set the Digita l
resistance check
•
Probe each end of the wire.
•
If there is conti n uity, the meter will usually
bleep or register the resistance of the cable.
•
A high resistance figu re could indicate a dirty
or corroded connection.
'
If there is a break in the wire, the meter will
not bleep or register a resistance.
•
By probing the wire in various places, the
position of a high resistance or break in the
wire (open ci rcuit> can be narrowed down
u ntil it is found.
800 and 800XC
Tiger
M ulti Meter <DMM> to
(Q).