For 1990-2009 cars

## Powertrain Control Module Inputs Diagnosis Engine Oil Pressure Switch

Refer to

#### IAC Valve, Generator, TR, Oil, and Coolant Switches

Engine Controls Components
Information Sensors/Switches Description
VSS and Cruise Control
Oxygen Sensors
OBDII Symbol Description Notice
Handling Electrostatic Discharge Sensitive Parts Notice
schematic.

### Circuit Description

The Engine Oil Pressure Indicator is controlled by the Instrument Panel Cluster (IPC) via serial data from the Powertrain Control Module (PCM) . The Oil Pressure Indicator will also light when the engine is running if the engine oil pressure drops below approximately 13.8 kPa. (2 psi.).

As a bulb check procedure, the IPC will command this telltale ON when the IPC and PCM are powered up.

Step | Action | Value(s) | Yes | No
--- | --- | --- | --- | ---
1 | Was the Powertrain On-Board Diagnostic (OBD) System Check performed? | -- | Go to Step 2 | Go to Powertrain On Board Diagnostic (OBD) System Check
2 | Are any PCM DTC(s) stored? | -- | Go to applicable DTCs | Go to Step 3
3 | Is the Engine Oil pressure Indicator ON? | -- | Go to Step 4 | Go to Step 12
4 | Check the engine for correct oil level. Refer to Fluid and Lubricant Recommendations in Maintenance and Lubrication. Is the Correct engine oil level indicated? | -- | Go to Step 5 | Go to Step 10
5 | Check the engine oil pressure with a manual pressure gauge. Refer to Oil Pressure Diagnosis and Testing in Engine Mechanical. Is proper engine oil pressure indicated? | -- | Go to Step 6 | Go to Step 11
6 | Disconnect the PCM harness connector and the Engine Oil Pressure Sensor Connector and check the oil pressure sensor input circuit for the following:

• | Open circuit

• | Shorts to ground

• | Short to battery positive voltage

• | Check for poor or corroded connections.

If a problem is found repair as necessary. Refer to Wiring Repairs in Wiring Systems.

Was a Problem Found?

--

Go to Step 12

go to step 7

7 | Check the Communication circuit for correct operation. Was a problem Found? | -- | Go to Step 12 | go to step 8
8 | Check engine oil pressure sensor indicator for correct operation. Refer to Instrument Cluster System Check in Instrument Panel, Gauges and Console. If a problem is found repair as necessary. Was a problem found? | -- | Go to Step 12 | Go to Step 9
9 | Replace Engine Oil Pressure Sensor. Is the action complete? | -- | Go to Step 12 | --
10 | Determine cause of low oil. Refer to Oil Consumption Diagnosis Engine Mechanical. Is the action complete? |  | Go to Step 12 | --
11 | Determine cause of low oil pressure. Refer to Oil Pressure Diagnosis and Testing in Engine Mechanical. Is the action complete? |  | Go to Step 12 | --
12 | Check for the proper operation of Oil Pressure Indicator. Refer to Instrument Cluster System Check in Instrument Panel, Gauges and Console. Is the correct operation indicated? |  | System OK | go to step 2