Pinpoint Test K: The Low Oil Pressure Message Center Warning Indicator Is Never/Always On
Instrumentation, Message Center and Warning Chimes
Pinpoint Test K: The Low Oil Pressure Message Center Warning Indicator Is Never/Always On
Refer to Wiring Diagram Set 60, Instrument Cluster for schematic and connector information. Diagrams By Number
Normal Operation
The Instrument Panel Cluster (IPC) provides a reference voltage to the engine oil pressure switch. When the oil pressure is within normal ranges, the engine oil pressure switch closes to ground, pulling the reference voltage low in the IPC. The IPC senses the low reference voltage and turns off the low oil pressure message center warning indicator. When the engine oil pressure is low, the engine oil pressure switch opens, sending the reference voltage high in the IPC. The IPC senses the high voltage and turns the low oil pressure message center warning indicator on. The engine must be running with the rpm above 400 rpm for the low oil pressure message center warning indicator to be displayed in the IPC message center.
This pinpoint test is intended to diagnose the following:
- Wiring, terminals or connectors
- Tachometer indication concern
- Engine oil pressure switch
- Base engine oil pressure concern
- IPC
PINPOINT TEST K: THE LOW OIL PRESSURE MESSAGE CENTER WARNING INDICATOR IS NEVER/ALWAYS ON
NOTICE: Use the correct probe adapter(s) when making measurements. Failure to use the correct probe adapter(s) may damage the connector.
-------------------------------------------------
K1 CHECK THE TACHOMETER OPERATION
- Start the engine and monitor the tachometer.
- Check that the engine speed is more then 400 rpm.
- Does the tachometer operate correctly?
Yes
GO to K2.
No
GO to Pinpoint Test J. Pinpoint Test J: Incorrect Tachometer Indication
-------------------------------------------------
K2 CHECK THE MESSAGE CENTER WARNING INDICATOR FUNCTION
- Close all doors and the luggage compartment lid.
- Ignition ON.
- Open the driver door while monitoring the door ajar message center displays.
- Does the door ajar message center warning indicator remain off with the door closed and display with the door open?
Yes
If the low oil pressure message center warning indicator is never on, GO to K3.
If the low oil pressure message center warning indicator is always on, GO to K5.
No
GO to Pinpoint Test T. Pinpoint Test T: The Door Ajar Message Center Warning Indicator Is Never/Always On
-------------------------------------------------
K3 CHECK FOR A STUCK CLOSED ENGINE OIL PRESSURE SWITCH
- Ignition OFF.
- Disconnect: Engine Oil Pressure Switch C103.
- Start the engine to provide an rpm signal to turn on the message center warning indicator (RTT).
- Observe the low oil pressure warning indicator.
- Does the low oil pressure message center warning indicator turn on?
Yes
INSTALL a new Engine Oil Pressure (EOP) switch. REFER to Engine. TEST the system for normal operation.
No
GO to K4.
-------------------------------------------------
K4 CHECK THE OIL PRESSURE INPUT CIRCUIT FOR A SHORT TO GROUND
- Ignition OFF.
- Disconnect: IPC C220.
- Measure the resistance between the IPC C220-6, circuit CMC24 (GY), harness side and ground.
- Is the resistance greater than 10,000 ohms?
Yes
GO to K8.
No
REPAIR circuit CMC24 (GY) for a short to ground. TEST the system for normal operation.
-------------------------------------------------
K5 CHECK FOR A STUCK OPEN ENGINE OIL PRESSURE SWITCH
- Ignition OFF.
- Disconnect: Engine Oil Pressure Switch C103.
- Connect a fused jumper wire between the engine oil pressure switch, C103-1, circuit CMC24 (GY), harness side and ground.
- Start the engine.
- Observe the low oil pressure message center warning indicator.
- Does the low oil pressure message center warning indicator turn off?
Yes
REMOVE the jumper wire. GO to K7.
No
LEAVE the jumper wire connected. GO to K6.
-------------------------------------------------
K6 CHECK THE OIL PRESSURE SWITCH INPUT CIRCUIT FOR AN OPEN
- Ignition OFF.
- Disconnect: Negative Battery Cable.
- Disconnect: IPC C220.
- With the jumper wire in place, measure the resistance between the IPC C220-6, circuit CMC24 (GY), harness side and ground.
- Is the resistance less than 5 ohms?
Yes
REMOVE the jumper wire. GO to K7.
No
REMOVE the jumper wire. REPAIR circuit CMC24 (GY) for an open. TEST the system for normal operation.
-------------------------------------------------
K7 CHECK THE OIL PRESSURE
- Carry out the oil pressure test. Refer to Engine. Oil Pressure Test
- Is the oil pressure within specification?
Yes
INSTALL a new EOP switch. REFER to Engine.
No
REFER to Engine to continue diagnosis of the low engine oil pressure concern.
-------------------------------------------------
K8 CHECK FOR CORRECT IPC OPERATION
- Disconnect the IPC connector.
- Check for:
- corrosion
- damaged pins
- pushed-out pins
- Connect the IPC connector and make sure it seats correctly.
- Operate the system and verify the concern is still present.
- Is the concern still present?
Yes
INSTALL a new IPC. REFER to Instrument Panel Cluster (IPC) Instrument Panel Cluster (IPC). TEST the system for normal operation.
No
The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector.
-------------------------------------------------