
Diagnostic procedure

Dtc c1508
Dtc u2021Mazda 6 Service Manual: Engine control system operation inspection
Main Relay Operation Inspection
Verify that the main relay clicks when the ignition switch is turned to ON
position and off.
If there is no operation sound, inspect the following.
- Main relay (See RELAY INSPECTION.)
- Harness and connector between ignition switch and main relay termi ...
Mazda 6 Service Manual: Precaution
Vehicles with ABS/TCS
1. The ABS warning light, BRAKE system warning light, TCS indicator light
and/or TCS OFF light illuminate even when the system is normal.
*1 : In cases where the light may illuminate, only when ABS/TCS HU/CM detects
that speed sensor of rear wheel is malfunctioning.
*2 ...