Pinpoint Test K: Incorrect Oil Pressure Gauge Indication
Instrumentation, Message Center and Warning Chimes
Pinpoint Test K: Incorrect Oil Pressure Gauge Indication
Normal Operation
The Instrument Panel Cluster (IPC) provides a reference voltage to the oil pressure switch on the input circuit. When the oil pressure is within normal ranges, the engine oil pressure switch closes to ground pulling the reference voltage low to the IPC (Instrument Panel Cluster). The IPC (Instrument Panel Cluster), upon receipt of the ground signal, commands the oil pressure gauge to the normal or mid-range position. When the oil pressure is low, the engine oil pressure switch opens, removing the ground, and the IPC (Instrument Panel Cluster) commands the oil pressure gauge to the L (low) position.
This pinpoint test is intended to diagnose the following:
- Wiring, terminals or connectors
- Engine oil pressure switch
- Base engine concern
- IPC (Instrument Panel Cluster)
PINPOINT TEST K : THE OIL PRESSURE GAUGE IS INOPERATIVE
NOTICE: Use the correct probe adapter(s) when making measurements. Failure to use the correct probe adapter(s) may damage the connector.
NOTE: Failure to disconnect the battery when instructed will result in false resistance readings.
K1 CARRY OUT THE IPC (Instrument Panel Cluster) OIL PRESSURE GAUGE ACTIVE COMMAND USING THE SCAN TOOL
- Ignition ON.
- Enter the following diagnostic mode on the scan tool: IPC (Instrument Panel Cluster) DataLogger.
- NOTE: Make sure to set the scan tool to low (L) before beginning this step.
Select the IPC (Instrument Panel Cluster) oil pressure gauge (OIL_PRESS) active command and scroll the gauge according to the following table:
Oil Pressure Gauge Command Gauge Position 20% Start of the normal band 50% Just left of center (mid-range) 90% End of the normal band 100% High
Does the oil pressure gauge operate according to the above specifications?
Yes
If the oil pressure gauge always reads in the normal range, GO to K2.
If the oil pressure gauge always reads low (L) and does not register any oil pressure, GO to K4.
No
GO to K7.
K2 CHECK FOR A STUCK CLOSED ENGINE OIL PRESSURE SWITCH
- Ignition OFF.
- Disconnect: Engine Oil Pressure Switch C103.
- Ignition ON.
- Observe the engine oil pressure gauge.
Does the engine oil pressure gauge indicate low (L) oil pressure?
Yes
INSTALL a new Engine Oil Pressure (EOP) switch. TEST the system for normal operation.
No
GO to K3.
K3 CHECK THE INPUT CIRCUIT FOR A SHORT TO GROUND
- Ignition OFF.
- Disconnect: IPC (Instrument Panel Cluster) C220.
- Measure the resistance between the IPC (Instrument Panel Cluster) C220-22, circuit CMC24 (GY), harness side and ground.
Is the resistance greater than 10,000 ohms?
Yes
GO to K7.
No
REPAIR the circuit. TEST the system for normal operation.
K4 CHECK FOR A STUCK OPEN ENGINE OIL PRESSURE SWITCH
NOTE: If the fused jumper wire fails, repair circuit CMC24 (GY) for a short to voltage.
- 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 engine oil pressure gauge.
Does the engine oil pressure gauge indicate normal oil pressure?
Yes
REMOVE the jumper wire. GO to K6.
No
LEAVE the jumper wire connected. GO to K5.
K5 CHECK THE INPUT CIRCUIT FOR AN OPEN
- Ignition OFF.
- Disconnect: Negative Battery Cable.
- Disconnect: IPC (Instrument Panel Cluster) C220.
- With the jumper wire in place, measure the resistance between the IPC (Instrument Panel Cluster) C220-22, 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 the circuit. TEST the system for normal operation.
K6 CHECK THE OIL PRESSURE
- Carry out the engine oil pressure test. Oil Pressure Test
Is the oil pressure within specification?
Yes
INSTALL a new Engine Oil Pressure (EOP) switch. TEST the system for normal operation.
No
REFER to Engine to continue diagnosis of the engine oil pressure.
K7 CHECK FOR CORRECT IPC (Instrument Panel Cluster) OPERATION
- Disconnect the IPC (Instrument Panel Cluster) connector.
- Check for:
- corrosion
- damaged pins
- pushed-out pins
- Connect the IPC (Instrument Panel Cluster) 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 (Instrument Panel Cluster). REFER to 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. TEST the system for normal operation.