Low Oil Pressure Indicator Circuit Troubleshooting (Open)

1. Connect the HDS to the DLC (see step 2 on HOW TO USE THE HDS (HONDA DIAGNOSTIC SYSTEM) ).
2. Turn the ignition switch to ON (II).
3. Make sure the HDS communicates with the vehicle and the PCM. If it does not communicate, troubleshoot the DLC circuit (see DLC CIRCUIT TROUBLESHOOTING ).
4. Check for DTCs (see GENERAL TROUBLESHOOTING INFORMATION ). If a DTC is present, diagnose and repair the cause before continuing with this test.
5. Start the engine, and check the OIL PRESSURE SWITCH in the PGM-FI DATA LIST with the HDS.

   Is ON indicated? 

   YES  -Replace the gauge control module (see GAUGE CONTROL MODULE REPLACEMENT ).

   NO  -Go to step 6.

6. Turn the ignition switch to LOCK (0).
7. Check the oil pressure switch (see OIL PRESSURE SWITCH TEST ).

   Is the oil pressure switch OK? 

   YES  -Go to step 8.

   NO  -Do the pressure test (see OIL PRESSURE TEST ). If the oil pressure is OK, replace the oil pressure switch (see OIL PRESSURE SWITCH TEST ).

8. Turn the ignition switch to ON (II), jump the SCS line with the HDS, then turn the ignition switch to LOCK (0).
   NOTE: This step must be done to protect the PCM from damage.
9. Disconnect PCM connector C (49P) and the oil pressure switch connector.
10. Check for continuity between PCM connector terminal C45 and the oil pressure switch connector.

Fig 1: Checking Continuity Between PCM Connector Terminal C45 And Oil Pressure Switch Connector

Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there continuity? 

YES  -Update the PCM if it does not have the latest software (see PCM UPDATE ), or substitute a known-good PCM (see SUBSTITUTING THE PCM ), then recheck. If the symptom/indication goes away with a known-good PCM, replace the original PCM (see PCM REPLACEMENT ).

NO  -Repair an open in the wire between the oil pressure switch and the PCM.