diff --git a/lib/apds9960/apds9960/device.py b/lib/apds9960/apds9960/device.py
index e83efe82..6ace6bd8 100644
--- a/lib/apds9960/apds9960/device.py
+++ b/lib/apds9960/apds9960/device.py
@@ -230,8 +230,33 @@ def isLightAvailable(self):
 
         return val == APDS9960_BIT_AVALID
 
+    def isProximityAvailable(self):
+        val = self._read_reg(APDS9960_REG_STATUS)
+        return (val & APDS9960_BIT_PVALID) == APDS9960_BIT_PVALID
+
+    def _ensure_light_enabled(self):
+        enable = self.getMode()
+        if not (enable & (1 << APDS9960_MODE_AMBIENT_LIGHT)) or not (enable & APDS9960_BIT_PON):
+            self.enableLightSensor(interrupts=False)
+            for _ in range(50):
+                if self.isLightAvailable():
+                    return
+                sleep_ms(10)
+            raise OSError("APDS9960 light data ready timeout")
+
+    def _ensure_proximity_enabled(self):
+        enable = self.getMode()
+        if not (enable & (1 << APDS9960_MODE_PROXIMITY)) or not (enable & APDS9960_BIT_PON):
+            self.enableProximitySensor(interrupts=False)
+            for _ in range(50):
+                if self.isProximityAvailable():
+                    return
+                sleep_ms(10)
+            raise OSError("APDS9960 proximity data ready timeout")
+
     # reads the ambient (clear) light level as a 16-bit value
     def readAmbientLight(self):
+        self._ensure_light_enabled()
         # read value from clear channel, low byte register
         low = self._read_reg(APDS9960_REG_CDATAL)
 
@@ -242,6 +267,7 @@ def readAmbientLight(self):
 
     # reads the red light level as a 16-bit value
     def readRedLight(self):
+        self._ensure_light_enabled()
         # read value from red channel, low byte register
         low = self._read_reg(APDS9960_REG_RDATAL)
 
@@ -252,6 +278,7 @@ def readRedLight(self):
 
     # reads the green light level as a 16-bit value
     def readGreenLight(self):
+        self._ensure_light_enabled()
         # read value from green channel, low byte register
         low = self._read_reg(APDS9960_REG_GDATAL)
 
@@ -262,6 +289,7 @@ def readGreenLight(self):
 
     # reads the blue light level as a 16-bit value
     def readBlueLight(self):
+        self._ensure_light_enabled()
         # read value from blue channel, low byte register
         low = self._read_reg(APDS9960_REG_BDATAL)
 
@@ -276,6 +304,7 @@ def readBlueLight(self):
 
     # reads the proximity level as an 8-bit value
     def readProximity(self):
+        self._ensure_proximity_enabled()
         return self._read_reg(APDS9960_REG_PDATA)
 
     # *******************************************************************************
diff --git a/tests/scenarios/apds9960.yaml b/tests/scenarios/apds9960.yaml
index b19db006..b22bc617 100644
--- a/tests/scenarios/apds9960.yaml
+++ b/tests/scenarios/apds9960.yaml
@@ -79,6 +79,66 @@ tests:
     expect: 128
     mode: [mock]
 
+  # ----- Auto-enable -----
+
+  - name: "Auto-enable writes ENABLE register for light"
+    action: script
+    script: |
+      dev.disableLightSensor()
+      i2c.clear_write_log()
+      dev.readAmbientLight()
+      log = i2c.get_write_log()
+      wrote_enable = any(reg == 0x80 for reg, data in log)
+      enable_val = dev.getMode()
+      has_pon = bool(enable_val & 0x01)
+      has_aen = bool(enable_val & 0x02)
+      result = wrote_enable and has_pon and has_aen
+    expect_true: true
+    mode: [mock]
+
+  - name: "Auto-enable writes ENABLE register for proximity"
+    action: script
+    script: |
+      dev.disableProximitySensor()
+      i2c.clear_write_log()
+      dev.readProximity()
+      log = i2c.get_write_log()
+      wrote_enable = any(reg == 0x80 for reg, data in log)
+      enable_val = dev.getMode()
+      has_pon = bool(enable_val & 0x01)
+      has_pen = bool(enable_val & 0x04)
+      result = wrote_enable and has_pon and has_pen
+    expect_true: true
+    mode: [mock]
+
+  - name: "Auto-enable restores power for light read"
+    action: script
+    script: |
+      dev.disablePower()
+      i2c.clear_write_log()
+      dev.readRedLight()
+      log = i2c.get_write_log()
+      wrote_enable = any(reg == 0x80 for reg, data in log)
+      enable_val = dev.getMode()
+      has_pon = bool(enable_val & 0x01)
+      has_aen = bool(enable_val & 0x02)
+      result = wrote_enable and has_pon and has_aen
+    expect_true: true
+    mode: [mock]
+
+  - name: "No re-enable when already active"
+    action: script
+    script: |
+      dev.enableLightSensor(False)
+      i2c.clear_write_log()
+      dev.readAmbientLight()
+      log = i2c.get_write_log()
+      result = len(log) == 0
+    expect_true: true
+    mode: [mock]
+
+  # ----- Hardware -----
+
   - name: "Ambient light in plausible range"
     action: call
     method: readAmbientLight