by _Anders_ » Wed Jul 20, 2022 2:31 pm
Now its finally fixed.
And the culprit was the fan resistors.
So there is a pack of two huge resistors between the two fans for the air-conditioning condenser/cooling radiator. The power for the fans goes through few relays and get the signal from the PCM (and the other switches related to the system) i assume to power on. I tested both the fans with 12v so they were working. Then i removed the resistor pack from the fan casing and it was clear right away that its a gonner. It was so corroded that you could not see the parts in it. I tried to clean it gently but there was a component inside it and it was held only by corrosion and it fell off. I also tested the power to the resistors from the plug and there was almost instantly 13v in two of the three pins in it after i powered the ac on, so i assumed that that part was ok. Now to hunt a new resistor and It was harder than i thought. I could not find it new anywhere and had to resort to buying it from a scrapyard and i had to get the whole fan shroud with the fans to get the resistor. It seems the 2 fan model with 2 resistors is almost rare as hens teeth. But now its installed and the fans kicked right up after i powered the ac. So i call that a partial win.
But in conclusion it seems that the fan control does not have any logic to it regarding to the fans spinning or not in this model. If the voltage is going out it seems to think the fans are on. I still don't know if i have some part bad in the system because the compressor did not power off after the high pressure rising (or did the tech just play it safe at the garage and the high pressure switch didn't reach the maximum pressure limit? who knows..), but the both pressure switches are new, so now the system works and i am happy.
If someone knows where to acquire these resistors new, please tell me so ill get one for the future (2 fan model with 3cables/pins).
I just wanted to post this for future transit owners struggling with similar issues. Thanks for the suggestions and comments!