
Diagnostic Procedure

Dtc 18
Dtc 21Mazda 6 Service Manual: Instrument cluster inspection
Speedometer
Using the input/output check mode
Inspect the speedometer by setting it in the input/output check mode DTC 12.
Using a speedometer tester
1. Adjust the tire air pressure to the specification.
2. Using a speedometer tester, verify that the speedometer indication is
within the allow ...
Mazda 6 Service Manual: Engine Coolant Temperature Gauge
Displays the engine coolant temperature. The blue gauge indicates that the engine
coolant temperature is low, and the red gauge indicates that the engine coolant
temperature is high and overheating.
CAUTION
If the high engine coolant temperature warning light (red) turns on, there
is a pos ...