DOOSAN-CODE-5 critical Doosan/Ingersoll-Rand SECU portables

Engine Oil Pressure Switch (S5) Open — Shutdown

The DOOSAN-CODE-5 (Doosan/Ingersoll-Rand SECU portables) diesel fault code means: Engine Oil Pressure Switch (S5) Open — Shutdown. This is a critical severity code.

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Common Symptoms

  • Machine shuts down and SECU display shows code 5
  • Possible genuine loss of engine oil pressure

Probable Causes (Ranked by Likelihood)

  • Actual loss of engine oil pressure High
  • Faulty S5 oil pressure switch Moderate
  • Wiring fault between S5 and SECU (wires W008 / W089) Moderate

Step-by-Step Diagnostic Procedure

  1. This code set applies to SECU-display machines (7/51, 7/71, XP185, P260). Newer Tier-4-Final Doosan portables such as the P185WDOU-T4F use a DIFFERENT code set (CPR codes) — confirm which controller your machine has before acting on this page.

  2. CHECK THE ENGINE OIL LEVEL FIRST — the factory procedure starts there, because the SECU shuts the machine down if this switch is open for 1 second while running.

  3. Check continuity of wire W008 from S5 pin 2 to SECU controller pin 26.

  4. Check continuity of wire W089 from S5 pin 1 to splice E16.

  5. If oil level and wiring are good, replace the S5 switch (side of the engine block). Do not keep restarting against a possible real oil-pressure loss.

Frequently Asked Questions

What does code 5 mean?

The SECU detected an open S5 engine oil pressure switch for one second while running and shut the machine down. That either means real oil-pressure loss or a failed switch/wiring. Check the oil level before anything else, and treat repeated trips as a real lubrication problem until proven otherwise.

Sources

This page is built from documented references. Verify against your own service info before repair work.

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