AC Code B1973

[billydv]

Wanted to post this, surely someone else will run into this. Compressor wasn't turning on, code b1973 Compressor invalid signal. Turned out to be a bad pressostat. Couldn't find any info on that code anywhere.

 

[Maserlove]

I have the same code/issue.

Sometimes the AC does work, sometimes not.

I was googling the fault code and came across this thread. Nearly ordered right away a ne pressostat.

But I also saw this video

where it was this Fan Resistor with the same error code.

Since I have it as spare already at home I will first exchange this one and give it a try.

Let you guys now.

 

[Zep]

The reason it would have the same code for different parts is because it is saying the pressure is too high.

This could either be caused by the fan not working or because the pressure switch is faulty.

In the case above, the compressor would engage for a short period before the pressure went too high giving the fault. If the pressure switch is faulty the compressor would not engage at all. This can also be checked with refrigerant gauges if you have them and know how to use them.

 

[conaero]

Or there is too much gas in it. The book says 1100gm and it should be 600gm

 

[Maserlove]

My car was in the workshop and they filled 800g was the feedback.

When the AC was not working I had the feeling the AC compressor tries to engage. It was like on and off...also the rpm where rising and coming down again.

So the easiest way for me at the moment would be to exchange the resistor. If there is to much gas in the AC the system should be turned off after a while.

But if it´s on, it´s on.... to be honest I think it´s the sensor. It´s the only thing which could give different values.

All other mechanical things are working or not working. There is no self healing for mechanical parts.

 

[Zep]

If you have 800 grams, then you have too much. Whether it is the cause of your fault is another question, but in low temperatures it will suffer from liquid logging.