Circuit Description
The PCM applies battery voltage through a pull up resistor to the Engine Oil Pressure Switch circuit. The PCM monitors the applied voltage on the Engine Oil Pressure Switch circuit. If the ignition switch is turned ON with the engine not running or engine oil pressure is below 35 kPa (5 psi), the Engine Oil Pressure switch grounds the PCM voltage input. The PCM sends the engine oil pressure information via Class II serial data to the Instrument Panel Cluster (IPC). The IPC controls the Engine Oil Pressure Indicator.
Diagnostic Aids
Check for the following condition(s):
| • | Poor connections. Inspect PCM and harness connectors for backed out terminals, improper mating, broken locks, improperly formed or damaged terminals, and poor terminal to wire connection. |
| • | Damaged harness. Inspect the wiring harness for damage. If the harness appears to be OK, disconnect the Engine Oil Pressure switch, turn the ignition on and observe a DMM connected between the Engine Oil Pressure switch connector terminals while moving wiring harnesses related to the Engine Oil Pressure Switch circuit. A change in voltage will indicate the location of the fault. |
Step | Action | Value(s) | Yes | No | ||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
1 | Was the Powertrain On Board Diagnostic (OBD) System Check performed? | -- | ||||||||||
2 | Are any PCM DTC(s) stored? | -- | Diagnose the PCM DTC(s) first. Go to Powertrain Control Module Diagnosis | |||||||||
3 | Is the Engine Oil pressure Indicator on? | -- | ||||||||||
4 | Check the engine for correct oil level. Refer to General Information, Maintenance and lubrication. Is the Correct engine oil level indicated? | -- | ||||||||||
5 | Check the engine oil pressure with a manual pressure gauge. Refer to Engine Mechanical. Is proper engine oil pressure indicated? | -- | ||||||||||
6 | Disconnect the PCM harness connector and the Engine Oil Pressure Switch Connector and check the oil pressure sensor input circuit for the following:
If a problem is found repair as necessary. Refer to Repair Procedures in Electrical Diagnosis. Was a Problem Found? | -- | ||||||||||
7 | Check the Communication circuit for correct operation. Refer to Electrical Diagnosis. Was a problem Found? | -- | ||||||||||
8 | Check engine oil pressure switch indicator for correct operation. The PCM sends the engine oil pressure information via Class II serial data to the Instrument Panel Cluster (IPC). Refer to Instrument Panel Cluster. If a problem is found repair as necessary. Was a problem found? | -- | ||||||||||
9 | Replace Engine Oil Pressure Switch. Refer to Engine Oil Pressure Sensor . Is the action complete? | -- | -- | |||||||||
10 | Determine cause of low oil. Refer to Engine Mechanical for diagnosis. Is the action complete? | -- | ||||||||||
11 | Determine cause of low oil pressure. Refer to Engine Mechanical for diagnosis. Is the action complete? | -- | ||||||||||
12 | Check for the proper operation of Oil Pressure Indicator. Refer to Instrument Panel Cluster. Is the correct operation indicated? | System Ok |
