Pinpoint Test 3

Flow Chart No.3 - Symptom - Oil pressure reads inaccurately.

Step 1
Verify power at fuse panel - load side.




1. Using voltmeter, verity system voltage at load side of warning indicator Fuse 11 (7.5 A).




2. Is system voltage present at load side of fuse?

Step 2
Verify power at fuse panel - feed side.
1. Using voltmeter, verify system voltage at feed side of warning indicator Fuse 11 (7.5 A).




2. Is system voltage present at feed side of fuse?

Step 3
Verify power at cluster.




1. Partially remove cluster from instrument panel. Using voltmeter, verify system voltage at Pin 4 (R/Y) of the 16-pin cluster connector and gauge terminal.
2. Inspect cluster connector for damage.




3. Is voltage present at cluster connector and gauge terminal?

Step 4

CAUTION
^ Before checking the continuity of any circuit, make sure there is no voltage present in the circuit prior to switching the test equipment to the resistance function to avoid damage to equipment. Refer to test equipment user's manual for additional information.




1. Using ohmmeter, check continuity of the ground (B/W) wire at the 12-pin cluster connector to ground.




2. Is ground circuitry good?

Step 5
Test sender circuit at low.
1. Place key in the ON position with engine off. Observe gauge performance.




2. Does the gauge read L or below?

Step 6
Check gauge response.




1. Disconnect oil pressure sender and short the lead to engine ground.




2. Does the gauge indicate approximately mid-scale or slightly above mid-scale (around the MAL in NORMAL)?

Step 7
Check sending unit/switch wiring.

CAUTION
^ Before checking the continuity of any circuit, make sure there is no voltage present in the circuit prior to switching the test equipment to the resistance function to avoid damage to equipment. Refer to test equipment user's manual for additional information.

1. Using an ohmmeter, check sending unit/switch wiring and instrument cluster printed circuit for shorts or opens by physically flexing the wiring and observing continuity. The continuity reading should not fluctuate.
2. Gauge will read beyond the normal band if not grounded.




3. Is wiring and instrument cluster printed circuit OK?