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Pinpoint Test R: The Low Oil Pressure Warning Indicator Is Never/Always On




Instrumentation, Message Center and Warning Chimes

Pinpoint Test R: The Low Oil Pressure Warning Indicator Is Never/Always On (Non-Hybrid)

Refer to Wiring Diagram Set 60, Instrument Cluster for schematic and connector information Electrical Diagrams.

Normal Operation

The Instrument Cluster (IC) 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 IC (Instrument Cluster). The IC (Instrument Cluster) senses the low reference voltage and turns off the low oil pressure warning indicator. When the engine oil pressure is low, the engine oil pressure switch opens, sending the reference voltage to the normal voltage in the IC (Instrument Cluster). The IC (Instrument Cluster) senses the normal reference voltage and turns the low oil pressure warning indicator on.

This pinpoint test is intended to diagnose the following:

- Wiring, terminals or connectors

- Engine oil pressure switch

- Low engine oil pressure

- IC (Instrument Cluster)

PINPOINT TEST R : THE LOW OIL PRESSURE WARNING INDICATOR IS NEVER/ALWAYS ON (NON-HYBRID)

NOTICE: Use the correct probe adapter(s) when making measurements. Failure to use the correct probe adapter(s) may damage the connector.

R1 CARRY OUT THE IC (Instrument Cluster) INDICATOR LAMP CONTROL ACTIVE COMMAND USING THE SCAN TOOL

- Ignition ON.

- Enter the following diagnostic mode on the scan tool: IC (Instrument Cluster) DataLogger.

- Select the IC (Instrument Cluster) low oil pressure warning indicator (OIL_P_L) active command. Command the low oil pressure warning indicator on and off. Observe the low oil pressure warning indicator.

Does the low oil pressure warning indicator illuminate when commanded on and turn off when commanded off?

Yes
If the low oil pressure warning indicator is always on, GO to R2.

If the low oil pressure warning indicator is never on, GO to R6.

No
GO to R8.

R2 CHECK THE ENGINE OIL PRESSURE SWITCH OPERATION

- 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.





- Ignition ON.

- Monitor the low oil pressure warning indicator.

Does the low oil pressure warning indicator turn off?

Yes
REMOVE the jumper wire. GO to R3.

No
REMOVE the jumper wire. GO to R4.

R3 CARRY OUT THE ENGINE OIL PRESSURE TEST

- Carry out the engine oil pressure test Oil Pressure Test.

Is the engine oil pressure within specification?

Yes
INSTALL a new Engine Oil Pressure (EOP) switch. TEST the system for normal operation.

No
REFER to Engine.

R4 CHECK THE OIL PRESSURE INPUT CIRCUIT FOR A SHORT TO VOLTAGE

- Ignition OFF.

- Disconnect: IC (Instrument Cluster) C220.

- Ignition ON.

- Measure the voltage between the IC (Instrument Cluster) C220-6, circuit CMC24 (GY), harness side and ground.





Is any voltage present?

Yes
REPAIR circuit CMC24 (GY) for a short to voltage. TEST the system for normal operation.

No
GO to R5.

R5 CHECK THE OIL PRESSURE INPUT CIRCUIT FOR AN OPEN

- Ignition OFF.

- Measure the resistance between the IC (Instrument Cluster) C220-8, circuit CMC24 (GY), harness side and the engine oil pressure switch C103-1, circuit CMC24 (GY), harness side.





Is the resistance less than 5 ohms?

Yes
GO to R8.

No
REPAIR circuit CMC24 (GY) for an open. TEST the system for normal operation.

R6 CHECK THE ENGINE OIL PRESSURE SWITCH OPERATION

- Ignition OFF.

- Disconnect: Engine Oil Pressure Switch C103.

- Ignition ON.

- Monitor the low oil pressure warning indicator with the engine oil pressure switch disconnected.

Does the low oil pressure warning indicator turn on?

Yes
INSTALL a new Engine Oil Pressure (EOP) switch. TEST the system for normal operation.

No
GO to R7.

R7 CHECK THE OIL PRESSURE INPUT CIRCUIT FOR A SHORT TO GROUND

- Ignition OFF.

- Disconnect: IC (Instrument Cluster) C220.

- Measure the resistance between the IC (Instrument Cluster) C220-6, circuit CMC24 (GY), harness side and ground.





Is the resistance greater than 10,000 ohms?

Yes
GO to R8.

No
REPAIR circuit CMC24 (GY) for a short to ground. TEST the system for normal operation.

R8 CHECK FOR CORRECT IC (Instrument Cluster) OPERATION

- Disconnect the IC (Instrument Cluster) connector.

- Check for:
- corrosion

- damaged pins

- pushed-out pins


- Connect the IC (Instrument Cluster) connector and make sure it seats correctly.

- Operate the system and determine if the concern is still present.

Is the concern still present?

Yes
INSTALL a new IC (Instrument Cluster). REFER to Instrument Cluster (IC) . 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.