4200 Display "E" (AIR CONDITIONING no heating)

[muenchi12]

Hello everyone,

I have a problem with my Maserati 4200 CC. The actuator for the hot/cold flap is no longer turning. I am getting fault codes AA84 and AA55. The motor and the flap move with a 9V battery. Where could the errors be? Sorry for my slow English, I'm from Germany.

Thanks,
Tim

 

[CatmanV2]

Your external temperature sensor has probably failed. It's in the driver's door mirror

C

 

[muenchi12]

Your external temperature sensor has probably failed. It's in the driver's door mirror

C

Thank you for your response. The temperature on the Speedometer seems to be displayed correctly (I think). Is that also the sensor in the mirror?

Thanks

 

[Gp79]

Is there feedback on the actuators? It might move but feedback is the issue.
Also worth checking internal temp sensor as this is also relatively easy to remove / swap

 

[Gp79]

There must be some feedback with amount of circuits

 

[muenchi12]

Is there feedback on the actuators? It might move but feedback is the issue.
Also worth checking internal temp sensor as this is also relatively easy to remove / swap

Thank you, I'll check later on the other 3 contacts if there is any feedback. How can I test the interior sensor? I measured 12V on red/black and found resistance on the gray one.

 

[muenchi12]

 

[Gp79]

For the interior temp sensor if it were me I’d try I’d find a cheap spare to quickly test.

 

[CatmanV2]

Thank you for your response. The temperature on the Speedometer seems to be displayed correctly (I think). Is that also the sensor in the mirror?

Thanks

It is, so perhaps not that. I've never heard of an interior one failing, however.

C

 

[muenchi12]

Thank you very much, I measured the actuator today, there is continuity at the 3 contacts, depending on whether you move left or right.

Today I disconnected all sensors and actuators one by one... Each time, a different error code appears. AA55/AA84 always remain, even when the actuator is disconnected. The cables from the motor to the panel are okay... Does anyone else have an idea?

Best regards, Tim

 

[CatmanV2]

Both of those indicate the mixing valve is having issues. Are you checking the correct actuator? Mine used to get arsy when the grease was cold which increased the required load to move it.

C