DOOSAN-CODE-2 critical Doosan/Ingersoll-Rand SECU portables

Separator Tank Temperature Switch (S2) Open — Overheat Shutdown

The DOOSAN-CODE-2 (Doosan/Ingersoll-Rand SECU portables) diesel fault code means: Separator Tank Temperature Switch (S2) Open — Overheat Shutdown. This is a critical severity code.

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Common Symptoms

  • Machine shuts down and SECU display shows code 2
  • Separator tank may be genuinely overheated

Probable Causes (Ranked by Likelihood)

  • Separator tank over-temperature — the S2 switch opens at 248°F High
  • Faulty S2 switch Moderate
  • Wiring fault between S2 and the SECU (wires W005 / W087) 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. Rule out genuine overheating first: oil level, cooler condition, ambient temperature.

  3. Check continuity of wire W005 from S2 pin 2 to SECU controller pin 21.

  4. Check continuity of wire W087 from S2 to splice E16.

  5. If wiring is continuous, replace the S2 switch (mounted in the side of the separator tank).

Frequently Asked Questions

What does code 2 mean?

The SECU detected an open S2 separator tank temperature switch — the high-temperature shutdown for the separator tank, which opens at 248°F. Either the tank overheated or the switch/wiring failed. Code 2 shuts the machine down.

Sources

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

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