From cf27f54e8105edc00694effd13aaff4169faa2b1 Mon Sep 17 00:00:00 2001
From: Ryan Howard <ryan.howard@opentrons.com>
Date: Thu, 12 Sep 2024 16:51:01 -0400
Subject: [PATCH] fix(api): default to both sensors on lld (#16247)

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# Overview

In hardware testing we were explicitly calling liquid_probe with a
defined probe, but the protocol engine wasn't doing this and it was
always defaulting to just the A1 nozzle. The expected behavior is that
both sensors should work in an OR configuration. This just adds a check
that if the # of nozzles > 1 to turn both on instead of just the A1
sensor.

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## Test Plan and Hands on Testing

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---
 api/src/opentrons/hardware_control/ot3api.py | 11 ++++++++++-
 1 file changed, 10 insertions(+), 1 deletion(-)

diff --git a/api/src/opentrons/hardware_control/ot3api.py b/api/src/opentrons/hardware_control/ot3api.py
index fc46f8ea9fc..78563c5c299 100644
--- a/api/src/opentrons/hardware_control/ot3api.py
+++ b/api/src/opentrons/hardware_control/ot3api.py
@@ -2683,6 +2683,15 @@ async def liquid_probe(
         self._pipette_handler.ready_for_tip_action(
             instrument, HardwareAction.LIQUID_PROBE, checked_mount
         )
+        # default to using all available sensors
+        if probe:
+            checked_probe = probe
+        else:
+            checked_probe = (
+                InstrumentProbeType.BOTH
+                if instrument.channels > 1
+                else InstrumentProbeType.PRIMARY
+            )
 
         if not probe_settings:
             probe_settings = deepcopy(self.config.liquid_sense)
@@ -2756,7 +2765,7 @@ async def liquid_probe(
                 height = await self._liquid_probe_pass(
                     checked_mount,
                     probe_settings,
-                    probe if probe else InstrumentProbeType.PRIMARY,
+                    checked_probe,
                     p_pass_travel + p_impulse_mm,
                 )
                 # if we made it here without an error we found the liquid