Regulation Pressure Transducer (PT2) Out of Limits — Shutdown
The DOOSAN-CODE-6 (Doosan/Ingersoll-Rand SECU portables) diesel fault code means: Regulation Pressure Transducer (PT2) Out of Limits — Shutdown. This is a critical severity code.
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- Yes, but fix soon
- DIY difficulty
- moderate
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Common Symptoms
- Machine shuts down and SECU display shows code 6
- Engine throttle control may hunt before the shutdown
Probable Causes (Ranked by Likelihood)
- Failed PT2 regulation pressure transducer High
- Loss of the 5V transducer supply Moderate
- Wiring fault on W001/W002/W003 between PT2 and the SECU Moderate
Step-by-Step Diagnostic Procedure
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.
Check for +5 VDC at pin 2 on PT2 — that is the correct supply voltage.
Check continuity of wire W001 to pin 6 on the SECU controller.
If supply and wiring are good, replace the PT2 transducer (located in the inlet valve piping). The SECU flags this code after 3 seconds of out-of-limits readings while running.
Frequently Asked Questions
What does PT2 do?
PT2 reads regulation pressure, which the SECU uses to control engine throttle. When its reading is out of limits for 3 seconds with the machine running, the SECU shuts down — so a failed transducer can also show up first as odd throttle behaviour.
Sources
This page is built from documented references. Verify against your own service info before repair work.
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