Balboa · BP series (TP400, TP600, TP800, TP900, spaTouch panels)Stop using the tub

GFCI FAIL on a Balboa hot tub: gfci test failed

The control tried to trip the GFCI as a self-test and the breaker did not trip. That may mean the tub is not properly protected against electric shock. Do not use the tub until an electrician checks it.

Also shown as: M036, The GFCI test failed, System could not test the GFCI

Most likely causes

  1. 1GFCI breaker is faulty or worn outmost likely
  2. 2Tub is wired to a non-GFCI breakercommon
  3. 3Wiring fault between the GFCI and the spa (often the neutral or ground)common
  4. 4GFCI test feature enabled on a system that should not use itless common

What to try, in order

  1. Stay out of the water.
  2. Press the TEST button on the GFCI breaker at the disconnect. A good GFCI trips immediately.
  3. If the breaker does not trip on its own TEST button, leave it off.
  4. Call a licensed electrician to check the GFCI and the supply wiring.

GFCI FAIL questions

What does M036 mean?

M036 means the spa's automatic GFCI test failed. The spa could not confirm that the GFCI breaker will trip when it should.

Is it safe to keep using the tub?

No. Treat it as unprotected until an electrician confirms the GFCI works.

Related codes

Balboa -- · Temperature not yet knownBalboa CHEK PH · Maintenance reminderBalboa CLN FLTR · Filter reminderBalboa CNFG FAIL · Configuration errorBalboa dr · Heater may be dryBalboa dry · Heater is dryBalboa Ecn · Economy modeBalboa FLO · Low water flow

General guidance. Follow your manufacturer's instructions; anything inside the control box is work for a licensed professional. Updated October 5, 2026.