I got this app a while back, and I was having issues testing the fan with it. I messaged the developer and he was able to fix that in an update. I was able to test both speeds of my fan, and it turned out I had the wires reversed (pig tail broke apart a long time ago).esl_97_850_T5 wrote: 20 Mar 2019, 14:26 Testing the radiator fan of 96-97 850 / 97-98 S70/V70/C70/XC70 whose ECM is Motronic 4.4 -- by forcing the fan on High or Low for a short time -- can also be performed by xiaotec "850 OBD-II" Android app V1.1.6. Presumably the more recent "850 OBD-II" versions also have the ability to control the radiator fan on 96-98 850/SVC70 with M44.
Much easier setup than Volvo 850 diag, and it's a very useful app for '96-'98 P80s.
