Low oil pressure indicator does not come on with the vehicle in the ON mode

Diagnostic procedure 

• 1. Do the symptom troubleshooting for low oil pressure indicator does not come on with the vehicle in the ON mode - Refer to: Engine Lubrication System Symptom Troubleshooting - Low oil pressure indicator stays on Engine Lubrication System Symptom Troubleshooting - Low oil pressure indicator does not come on with the vehicle in the ON mode  .
• 2. Test the oil pressure switch .

Also check for 

An open in the wire between the PCM and the oil pressure switch