Acorn 180 curved fault code H4: Second processor fault

CodeH4 INFERRED
MeaningSecond processor fault
Control board180 curved (ex Bison 80) – T565 display CONFIRMED
How it showsLetter + number on display under the seat
Likely part needed: Controller INFERRED – only if the checks below point to it. Find it ›

Likely causes

Board

Step-by-step checks

  1. Engineer

Stairlift faults that stay after these checks are a job for a trained engineer.

Parts that usually fix this INFERRED

Matched by ScootScan from the fault description to parts listed for models that use this control board. Do the checks first – many faults are fixed by charging, a loose plug or a reset – and check the part fits your model before ordering.

Acorn 180 Main PCB
Controller listed for the Acorn 180 curved
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Models using this control board

Other Acorn 180 curved codes

Blank · A1 · A9 · E1 · E2 · E3 · E4 · E5 · E6 · E7 · F5 · F7 · C2 · C3 · C5 · E8 · E9 · F1 · F2 · F3 · F4 · F6 · F8 · F9 · H1 · H2 · H3 · H4 · H5 · H6 · H7 · H8 · H9 · J1 - J3 · J4 - J8

All Acorn 180 curved codes ›

Source: anglian-lifts.co.uk/acorn-180-curved-stairlift-error-codes-faults-expl ↗

Summarised from public manuals. Always check the product's own manual before any repair.