How do I check the elect. circuit on the wiring of an oil pressure sending unit? on 2007 Chevrolet Suburban 1500

Before replacing an oil pressure switch, a professional mechanic will first determine that the oil level and condition are okay, that the oil light electrical circuit is operating normally, and most importantly, that the oil pressure is within the manufacturer's specifications.

by in San Antonio, TX on March 18, 2012
2 answers 6 comments
ANSWER by on March 18, 2012
ground the sending unit wire while disconnected from sending unit and the gauge should go to max pressure
COMMENT by on March 18, 2012
Right now before I disconnect it while driving in goes all the way to the right at max and sometimes stays all the way to the left. I guess you are telling me to disconnect the wires from the sending unit and then ground the wires coming from the instrument panel correct?
COMMENT by on March 18, 2012
go to auto zone and have codes scanned for free and post them for us and we can try and help
COMMENT by on March 18, 2012
P0521-Engine Oil Pressure Sensor Range Performance P0523-Engine Oil Pressure Sensor Circuit High Voltage
COMMENT by on March 18, 2012
it sounds like you may have a gauge problem. does your mech have a tech 11 scanner so he can do a gauge sweep test. yes grd the wires at the sending unit and watch your gauge it should peg rt when disc. from sending unit it should go all the way left
COMMENT by on March 19, 2012
I detached the wires from the Oil Pressure sending unit and tried to clip the wires to ground them. The wires have three prongs coming out of the end that are grouped together and it was very difficult just to attach the clips to the end. Am I to try to attach the clips to all three or just one of them to ground it? When the wires are attached to the Oil Pressure Sensor the gauge goes all the way to the right when the car is turned on. When they are detached it stays all the way to the left. I tried to ground it and it did not move.
ANSWER by on March 18, 2012
Problem Description: P0521 & P0523. GAUGE INOP AND ENGINE LIGHT ON. CHECK OUT & REPLACED OIL PRESSURE SENSOR AND SCREEN BELOW IT. SAVE YOURSELF SOME TIME AND ORDER A NEW SCREEN AS IT WILL LIKELY TEAR WHEN YOU TRY TO GET IT OUT TO CLEAN IT. NOTE - NEED TO REMOVE INTAKE TO GET AT IT.
COMMENT by on March 19, 2012
The parts website only shows a Melling/Oil Pump Screen. I don't think it is the screen you are talking about. How much do you think it will cost me to have someone replace the screen when they replace the oil pressure sending unit? Also, I detached the wires from the Oil Pressure sending unit and tried to clip the wires to ground them. The wires have three prongs coming out of the end that are grouped together and it was very difficult just to attach the clips to the end. Am I to try to attach the clips to all three or just one of them to ground it? When the wires are attached to the Oil Pressure Sensor the gauge goes all the way to the right when the car is turned on. When they are detached it stays all the way to the left. I tried to ground it and it did not move.