Mazda Demio DY3W E/G Check Lamp Lit

2005 Mazda Demio DY3W Engine Model ZJ-VE

Situation
Engine Check Lamp illuminted.
The car run smoothly.

Cause
Faulty O2 sensor

Maintenance
Diagnosis noticed cord P0031that meant faulty of O2 sensor system.
Then I changed new O2 sensor.

Mazda Demio Mazda2 DW3W Hold Lamp Blink

 2001 Mazda Demio Mazda2 DW3W Transmission Model FN4A-EL

Situation
Hold indicator lamp blinked on and off.
The engine hesitated on acceleration.
Diagnosis noticed P0500 which indicate speed sensor.

Cause
Faulty Speed Sensor

Maintenance
Firstly I checked diagnosis system , It noticed P0500( Speed Sensor).
Then I rotated front tiyers by hand , checked voltage of Speed sensor at ECU 3T terminal.
The voltage was erratically , not 5V constantly.
Then I judged that Speed sensor was faulty and changed new Speed sensor.

It become properly.