Mazda RX-8 Workshop Manual page 3351

2 Is aftermarket electronic equipment
(two-way radio, navigation system,
mobile phone, etc.) installed?
3 Remove aftermarket electronic
equipment.
Turn audio unit/car-navigation unit
ON and check reception condition.
Is reception improved?
4 Measure battery voltage.
Is battery voltage okay?
Specification:
With ignition switch ON: 11.5 V
or more
At idling: 12.5 V or more
NOTE:
Inspect that battery cables are
connected to terminals securely.
5 Is noise occurring only when vehicle
electrical system (e.g. fuel pump)
operates?
NOTE:
Identify subject electrical component
by disconnecting fuse, turning switch
ON & OFF, or disconnecting &
connecting connector.
It will be easy when simulation
function on M-MDS is used.
6 Inspect power supply, ground
condition, and noise prevention
capacitor for electrical component.
Is noise present after inspection?
NOTE:
No Go to the next step.
YesGo to the next step.
No Go to Step 4.
YesThe system is normal. (Explain to
customers that aftermarket electronic
equipment is cause of noise)
No Go to the next step.
YesGo to the next step.
No Charge battery. Inspect charging system,
and repair or replace if necessary.
YesGo to the next step.
No Go to Step 7.
YesGo to the next step.
No Troubleshooting completed.