Test TG: Oil Pressure Gauge Always Reads Low & Gives Driver Alert; Erratic Oil Pressure Indication

NOTE: Verify engine oil level is not low and oil pressure is okay by using manual service gauge.

Check Oil Pressure Wiring

Disconnect oil pressure sending unit connector. Connect jumper wire between connector terminal and ground. Turn ignition switch to RUN position. If oil pressure gauge is reading normal, remove jumper wire and go to next step. If oil pressure gauge display has top 2 and bottom 2 bars are illuminated and oil ISO symbol is blinking, remove jumper wire and go to step 3 .

Check Wiring At Cluster

Disconnect negative battery cable. Remove Electronic Instrument Cluster (EIC). See ELECTRONIC INSTRUMENT CLUSTER under REMOVAL & INSTALLATION. Using DVOM, ensure continuity exists in White/Red wire between EIC connector "B" terminal No. 5 (White/Red wire) and terminal of oil pressure sending unit connector. If continuity does not exist, repair open in White/Red wire between oil pressure sending unit and EIC. See Figure . If continuity exists, go to next step.

Check Sending Unit

Disconnect oil pressure sending unit connector. Reconnect negative battery cable. Start vehicle without revving engine. Using DVOM, measure resistance at terminal of oil pressure sending unit and engine ground. Increase and decrease engine RPM while monitoring DVOM display. Resistance displayed should be 0-5 ohms at all times. If resistance does not remain within limits, replace oil pressure sending unit. If resistance stays within 0-5 ohms go to next step.

Check Engine Ground

Disconnect negative battery cable. Measure resistance between oil pressure sending unit case and disconnected negative battery cable terminal. If reading is 0-5 ohms, replace EIC. See ELECTRONIC INSTRUMENT CLUSTER under REMOVAL & INSTALLATION. If reading is 5 ohms or more, check engine is properly grounded and check for loose or corroded ground connections.