2006 – 2009 Mazda5 vehicles with VINs lower than JM1CR ****** 348679 (produced before November 1, 2008)
With the A/C on during an extended drive, the vent air volume decreases and/or the vents start to blow warm air.
When the freeze-up occurs, the following symptoms may be present:
- During freeze-up, the low pressure side pipe will have frost on it, giving the appearance it is frozen.
- Allowing the evaporator to unfreeze will temporarily address the concern.
NOTE: There are other conditions that can create similar symptoms, which include:
- During acceleration (throttle valve opening angle 50% or more). The duration is 5 seconds.
- When ECT (engine coolant temperature) is 113°C (235°F). The system repeatedly turns on and off every 20 seconds until the ECT is less than approximately 110°C (230°F).
- When ECT is 117°C (242°F) or more. The system will remain off until the ECT decreases to less than 114°C (237°F). These conditions signify the engine is running hot and could be on the verge of overheating.
- Electrical or mechanical concerns that could restrict vent air flow, causing irregular operation of the blower motor, and/or engagement of the A/C compressor.
The cause of the evaporator freeze-up is product variation of the evaporator temperature sensor and uneven airflow across the evaporator. To correct the sensor, a short harness with a built-in resistor will need to be installed in series with evaporator temperature sensor circuit. This cord will correct it by reducing the measured value 1°C (1.8°F). To correct the airflow, a cabin filter with a built-in diffuser will need to be installed in place of the current filter.
Customers having this concern should have their vehicle repaired using the following repair procedure.
- Record the customer’s radio station presets.
- Disconnect the negative battery for at least one minute.
- Remove the side wall on the passenger side foot well.
- Remove the Passenger Juction Box.
NOTE: PJB module configuration does not need to be performed since the same module will be used.
- Remove the metal bracket.
- Disconnect the connector from the evaporator temperature sensor connector.
- Disconnect the power MOSFET (if equipped with automatic climate control).
- Remove the evaporator access cover from the A/C unit.
- Remove the upper and lower air filters from the A/C unit.
- Install the air filter with diffuser plate.
- Install the air filter.
NOTE: Make sure the arrows marked on the air filter are facing towards the rear of the vehicle.
- Install the evaporator access cover to the A/C unit.
- Install the short harness with resistor to the connector, then connect the evaporator temperature sensor connector to it.
- Reassemble in the reverse order of removal.
- Reconnect the negative battery cable.
- Enter the customer’s radio presets and set the clock.
|BP8P-61-J6X||Air Filter Set (with diffuser plate)||1|
|BPY1-61-545A||Short Harness (with resistor)||1|