Fan Control Module Inspection

Connect the M-MDS to the DLC-2.
Start and warm up the engine.
Monitor the engine coolant temperature with the M-MDS.

Fig 1: Locating Data Link Connector (DLC-2)
Courtesy of MAZDA MOTORS CORP.

Measure the voltage at terminal 2 of the fan control module connector (2 terminals) as shown in the table below.

If not within the specification, inspect the input signals from the following parts.
- Cylinder Head Temperature (CHT) sensor
- Refrigerant pressure switch (middle)
  
  Fig 2: Fan Control Module Connector End View
  Courtesy of MAZDA MOTORS CORP.

Single fan control module

INSPECTION CHART

Inspection

Result

Condition

A/C

Engine coolant temp.

IG SW ON or idling

OFF

Less than 96 °C {205 °F}

0 V (Fan stops.)

Idling

OFF

96-106 °C {205-223 °F}

4.11-10.29 V

Idling

ON⁽¹⁾

96-106 °C {205-223 °F}

Approx. 6.4 V

Idling

ON⁽²⁾

96-106 °C {205-223 °F}

Approx. 7.7 V

Idling

OFF

More than 106 °C {223 °F}

B+

⁽¹⁾	Refrigerant pressure switch (middle) is off.

⁽²⁾	Refrigerant pressure switch (middle) is on.

Dual fan control module

INSPECTION CHART

Inspection

Result

Condition

A/C

Engine coolant temp.

IG SW ON or idling

OFF

Less than 96 °C {205 °F}

0 V (Fan stops.)

Idling

OFF

96-106 °C {205-223 °F}

4.11-10.29 V

Idling

ON⁽¹⁾

96-106 °C {205-223 °F}

Approx. 6.6 V

Idling

ON⁽²⁾

96-106 °C {205-223 °F}

Approx. 7.5 V

Idling

OFF

More than 106 °C {223 °F}

B+

⁽¹⁾	Refrigerant pressure switch (middle) is off.

⁽²⁾	Refrigerant pressure switch (middle) is on.

If all the above parts are normal, replace the fan control module.