Honda 954 Service Manual page 478

TACHOMETER
INSPECTION
Remove the upper cowl (page 2-5).
Check for loose or poor contact terminals of the c o m
Connect the peak voltage adaptor to the tachometer
TOOLS:
Peak voltage adaptor
with commercially available digital multimeter
(impedance
CONNECTION: Yellow/Green
Start the engine and measure the tachometer input
peak voltage.
PEAK VOLTAGE: 10.5 V minimum
If the value is normal, replace the tachometer.
If the measured value is below 10.5 V, replace the
ECM.
If the value is
Remove the ECM cover (page 5-87) and disconnect
the ECM multi-connector.
Check for continuity between the tachometer terminal
and the ECM (26P/Black) connector Yellow/Green ter-
minals.
If there
open circuit.
If there is continuity, replace the combination meter
print board.
For tachometer replacement, see page 19-8; combina-
tion meter disassembly and assembly.
INS PECTl O N
Remove the fuel tank (page 5-59).
Drain the coolant (page 6-41.
Disconnect the wire connector from the ECT/thermo
sensor and remove the sensor.
(not available in
U.S.A.)
0 V , perform the following:
is no continuity, check the wire harness for an
I
or
and Ground
PEAK V ~ L T A G E ADAPTOR