diff --git a/openemc-firmware/src/bq25713.rs b/openemc-firmware/src/bq25713.rs
index 7788ffd..5cd6d21 100644
--- a/openemc-firmware/src/bq25713.rs
+++ b/openemc-firmware/src/bq25713.rs
@@ -510,7 +510,7 @@ where
         // Enable IDPM.
         self.modify(i2c, REG_CHARGE_OPTION_0_LO, |v| v | (1 << 1))?;
 
-        if self.chrg_ok {
+        if self.chrg_ok && limit.max_input_current_ma > 0 {
             defmt::trace!("Programming maximum input current {} mA", limit.max_input_current_ma);
 
             // Enable or disable ICO.
diff --git a/openemc-firmware/src/supply/max14636.rs b/openemc-firmware/src/supply/max14636.rs
index 040d2cc..036c205 100644
--- a/openemc-firmware/src/supply/max14636.rs
+++ b/openemc-firmware/src/supply/max14636.rs
@@ -65,7 +65,7 @@ impl Max14636 {
                     !chg_al_n_low,
                     !chg_det_low
                 );
-                PowerSupply::Unknown
+                PowerSupply::Disconnected
             }
         }
     }
diff --git a/openemc-firmware/src/supply/mod.rs b/openemc-firmware/src/supply/mod.rs
index 9a34fe8..cb507fd 100644
--- a/openemc-firmware/src/supply/mod.rs
+++ b/openemc-firmware/src/supply/mod.rs
@@ -72,7 +72,11 @@ pub enum PowerSupply {
 impl PowerSupply {
     /// Merge two power supply reports, returning the best available power.
     pub fn merge(&self, other: &Self) -> Self {
-        self.max(other).clone()
+        if *self == Self::Disconnected || *other == Self::Disconnected {
+            Self::Disconnected
+        } else {
+            self.max(other).clone()
+        }
     }
 
     /// Whether the power supply state is unknown.