Mazda CX-5 Service & Repair Manual: Low Engine Coolant Temperature Indicator Light (Blue)/High Engine Coolant Temperature Warning Light (Red)

Purpose

Low engine coolant temperature indicator light (blue)

• The low engine coolant temperature indicator light (blue) notifies the driver that the engine coolant temperature is low and vaporization of the fuel is difficult.

High engine coolant temperature warning light (red)

• The high engine coolant temperature warning light (red) notifies the driver that the engine coolant temperature is high and that there is the danger of overheating.

Function

Low engine coolant temperature indicator light (blue)

• The low engine coolant temperature indicator light (blue) illuminates when the engine coolant temperature is low.

• The illumination condition of the low engine coolant temperature indicator light (blue) is as shown in the figure.

  

  
  

High engine coolant temperature warning light (red)

• The high engine coolant temperature warning light flashes at 0.5 s intervals when the engine coolant temperature exceeds the set value, and illuminates if the temperature increases further.

• The flashing/illumination condition of the high engine coolant temperature warning light (red) is as shown in the figure.

  

  
  

Construction

• Illumination, flashing, or turning off of the low engine coolant temperature indicator light (blue)/high engine coolant temperature warning light (red) is controlled by the instrument cluster microcomputer based on the engine coolant temperature signal from the PCM.

• The low engine coolant temperature indicator light (blue)/high engine coolant temperature warning light (red) is set in the instrument cluster.

  

  
  

Operation

Low engine coolant temperature indicator light (blue)

1. When the ignition is switched ON (while engine is running), the instrument cluster receives (1) the engine coolant temperature signal from the PCM via the CAN signal.

2. The instrument cluster turns the transistor on (2) based on the engine coolant temperature signal.

3. When the transistor turns on, the ground circuit of the low engine coolant temperature indicator light (blue) is established and the low engine coolant temperature indicator light (blue) illuminates (3).

High engine coolant temperature warning light (red)

1. When the ignition is switched ON (while engine is running), the instrument cluster receives (1) the engine coolant temperature signal from the PCM via the CAN signal.

2. The instrument cluster turns the transistor on (2) intermittently for flashing and continuously for illumination based on the engine coolant temperature signal.

3. The high engine coolant temperature warning light (red) flashes (3) when the transistor is turned on intermittently, and it illuminates (3) when the transistor is turned on continuously.

Fail-safe

• Function not equipped.