06 Volvo cummins ISX cm870 oil pressure sensor shuts down engine connected or not

Hi
my friend have 06 Volvo with cummins ISX cm870 engine
hes been trying to fix it for over 2 weeks and can find the problem :/

he gets low oil pressure warning code and buzzer on the dashboard and the truck shuts down

we disconnected the oil pressure sensor and it still acts the same and shuts down the truck

we checked the oil pressure with gauge of the oil filter fitting and it show normal 20- 40 psi,

oil and filter is new,

oil temp sensor is new

and 2 new oil pressure sensors ( just in case first was not good )

I thought that when the oil pressure sensor is disconnected the truck should run fine


and on INSITE voltage on oil pressure sensor shows 0.66- 0.67V .. no matter if oil pressure sensor is connected or disconnected.

sometimes when engine shakes , the pressure sensor starts working for a second, and INSITE shows higher voltage on the sensor but just for a second


we checked cables that go from the sensor to engine ECU and everything seems to be ok until EECU..

DO they go anywhere else from EECU? maybe they are broken somewhere else or inside EECU??

Please any info will be greatly appreciated!


thank you!!

 

maybe but it clearly says oil pressure too low .. will check this crankcase pressure sensor
thank you!

 

I didnt find the problem , he sold this truck long time ago but will ask him if he has fixed it