D: Oil Pressure Reads Inaccurately

Pinpoint Test D - Oil Pressure Reads Inaccurately

D1 - Check Power At Cluster Circuit 640 (R/Y)

- Turn ignition switch to the OFF position.
- Partially remove instrument cluster.
- Turn ignition switch to RUN position.
- Using a multimeter check for voltage at cluster connector pin C2-6, circuit 640 (R/Y).

Is B+ present?

YES GO to D2.
NO SERVICE circuit 640 (R/Y) for open circuit. RESTORE vehicle. RETEST system.

D2 - Test Oil Pressure Sensor Circuit At Low

- Place ignition switch in the RUN position with engine OFF. Observe gauge performance.

Does gauge read "L" or below?

YES GO to D3.
NO GO to D4.

D3 - Check Gauge Response

- Disconnect oil pressure sensor and short the lead to engine ground.

Does gauge indicate mid-scale or slightly above mid-scale?

YES REPLACE oil pressure sensor. RESTORE vehicle. RETEST system.
NO GO to D4.

D4 - Check Circuit 31 (W/R) For Open Circuit

- Leave oil pressure input circuit shorted to ground.
- Turn ignition switch to the OFF position. Remove instrument cluster as outlined.
- Using an ohmmeter connected to a known good ground, connect second lead to connector pin C2-7.
- Measure resistance.

Is resistance 5 ohms or less?

YES SERVICE circuit 31 (W/R) for open circuit. RESTORE vehicle. RETEST system.
NO GO to D5.

D5 - Check Oil Pressure Gauge

- Disconnect instrument cluster connectors.
- Using a multimeter check gauge for continuity at contact clips.

Is there continuity at all clips?

YES GO to D6.
NO REPLACE oil pressure gauge. RESTORE vehicle. RETEST system.

D6 - Check Flex Circuit

- Reconnect cluster connectors.
- Using a multimeter check for continuity from gauge contact clips to cluster connectors per chart.

Connector Pin Circuit Circuit Function
C2-6 640 (R/Y) Ignition Voltage
C2-8 676 (PK/O) Gauge Ground
C2-7 31 (W/R) Oil Pressure Input

Is there continuity at all circuits?

YES REPLACE oil pressure gauge. RESTORE vehicle. RETEST system.
NO REPLACE flex circuit. RESTORE vehicle. RETEST system.