diff --git a/src/usr/local/emhttp/plugins/fanctrlplus2/include/Common.php b/src/usr/local/emhttp/plugins/fanctrlplus2/include/Common.php
index 23a7dee..2e60d7e 100644
--- a/src/usr/local/emhttp/plugins/fanctrlplus2/include/Common.php
+++ b/src/usr/local/emhttp/plugins/fanctrlplus2/include/Common.php
@@ -73,17 +73,9 @@ function normalize_chip_name(string $chip): string {
 
 function build_pwm_map(): array {
     $map = [];
-    foreach (glob("/sys/class/hwmon/hwmon*") as $dir) {
-        $name_file = "$dir/name";
-        if (!is_file($name_file)) continue;
-
-        $chip = normalize_chip_name(trim(file_get_contents($name_file)));
-
-        foreach (glob("$dir/pwm[0-9]") as $pwm_path) {
-            $pwmN = basename($pwm_path);
-            $real = realpath($pwm_path) ?: $pwm_path;
-            $map["$chip:$pwmN"] = $real;
-        }
+    foreach (list_pwm() as $pwm) {
+        if ($pwm['chip'] === '') continue;
+        $map[normalize_chip_name($pwm['chip']).':'.$pwm['name']] = $pwm['sensor'];
     }
     return $map;
 }
@@ -232,17 +224,26 @@ function migrate_cfg_and_labels(string $plugin): void {
 // END: Migrate hwmonX (cfg+labels)
 // ================================
 
-function list_pwm() {
+// The sensor is the resolved /sys/devices path: saved labels and controller
+// settings use it, and the /sys/class/hwmon/hwmonN link follows probe order.
+// Older drivers keep their attributes on the parent device instead.
+// "pwm[0-9]*" would also match pwm1_enable and friends, hence the regex.
+function list_pwm(string $hwmon_glob = '/sys/class/hwmon/hwmon*') {
   $out = [];
-  exec("find /sys/devices -type f -iname 'pwm[0-9]' -exec dirname \"{}\" + | uniq", $chips);
-  foreach ($chips as $chip) {
-    $name = is_file("$chip/name") ? trim(file_get_contents("$chip/name")) : '';
-    foreach (glob("$chip/pwm[0-9]") as $pwm) {
-      $out[] = ['chip' => $name, 'name' => basename($pwm), 'sensor' => $pwm];
+  foreach (glob($hwmon_glob) ?: [] as $hwmon) {
+    $name = '';
+    foreach ([$hwmon, "$hwmon/device"] as $dir) {
+      if (is_file("$dir/name")) $name = trim(file_get_contents("$dir/name"));
+      foreach (glob("$dir/pwm*") ?: [] as $pwm) {
+        if (!preg_match('/^pwm\d+$/', basename($pwm)) || !is_file($pwm)) continue;
+        $sensor = realpath($pwm) ?: $pwm;
+        $out[$sensor] = ['chip' => $name, 'name' => basename($pwm), 'sensor' => $sensor];
+      }
     }
   }
 
-  usort($out, fn($a, $b) => strcmp($a['name'], $b['name']));
+  $out = array_values($out);
+  usort($out, fn($a, $b) => strnatcmp($a['name'], $b['name']) ?: strcmp($a['sensor'], $b['sensor']));
   return $out;
 }
 
diff --git a/tests/pwm_discovery_test.php b/tests/pwm_discovery_test.php
new file mode 100644
index 0000000..b1e73de
--- /dev/null
+++ b/tests/pwm_discovery_test.php
@@ -0,0 +1,57 @@
+<?php
+
+require_once __DIR__ . '/../src/usr/local/emhttp/plugins/fanctrlplus2/include/Common.php';
+
+$failures = [];
+$root = realpath(sys_get_temp_dir()) . '/fcp_pwm_discovery_' . getmypid();
+
+$chip = function (string $hwmon, string $device, string $name, array $files) use ($root): void {
+    @mkdir("$root/devices/$device", 0777, true);
+    @mkdir("$root/class/hwmon", 0777, true);
+    symlink("$root/devices/$device", "$root/class/hwmon/$hwmon");
+    file_put_contents("$root/devices/$device/name", "$name\n");
+    foreach ($files as $f) touch("$root/devices/$device/$f");
+};
+$usb = 'usb1/1-14/1-14:1.0/0003:3904:F001.0005/hwmon/hwmon5';
+$chip('hwmon5', $usb, 'arctic_fan_controller',
+    ['pwm1', 'pwm2', 'pwm10', 'pwm1_enable', 'pwm10_enable', 'pwm1_auto_point1_pwm']);
+
+// Older drivers put the attributes on the parent device; hwmonN is a stub
+// that may or may not carry the name.
+$legacy = function (string $hwmon, string $device, string $name, bool $nameOnDevice) use ($root, $chip): void {
+    @mkdir("$root/devices/$device/hwmon/$hwmon", 0777, true);
+    symlink("$root/devices/$device", "$root/devices/$device/hwmon/$hwmon/device");
+    $chip($hwmon, "$device/hwmon/$hwmon", $name, []);
+    if ($nameOnDevice) {
+        unlink("$root/devices/$device/hwmon/$hwmon/name");
+        file_put_contents("$root/devices/$device/name", "$name\n");
+    }
+    touch("$root/devices/$device/pwm1");
+};
+$legacy('hwmon2', 'platform/w83627hf.656', 'w83627hf', true);
+$legacy('hwmon3', 'platform/it87.552', 'it8728', false);
+
+$pwms = list_pwm("$root/class/hwmon/hwmon*");
+
+$expected = [
+    ['chip' => 'it8728',                'name' => 'pwm1',  'sensor' => "$root/devices/platform/it87.552/pwm1"],
+    ['chip' => 'w83627hf',              'name' => 'pwm1',  'sensor' => "$root/devices/platform/w83627hf.656/pwm1"],
+    ['chip' => 'arctic_fan_controller', 'name' => 'pwm1',  'sensor' => "$root/devices/$usb/pwm1"],
+    ['chip' => 'arctic_fan_controller', 'name' => 'pwm2',  'sensor' => "$root/devices/$usb/pwm2"],
+    ['chip' => 'arctic_fan_controller', 'name' => 'pwm10', 'sensor' => "$root/devices/$usb/pwm10"],
+];
+// Labels and controller settings are keyed by the /sys/devices path, so a
+// /sys/class/hwmon/hwmonN path would orphan every saved one.
+if ($pwms !== $expected) {
+    $failures[] = "PWM channels must include pwm10 and legacy-layout channels, exclude per-channel attributes,\n"
+        . "sort numerically and use the resolved device path. Got:\n" . var_export($pwms, true);
+}
+
+exec('rm -rf ' . escapeshellarg($root));
+
+if ($failures) {
+    fwrite(STDERR, implode("\n", $failures) . "\n");
+    exit(1);
+}
+
+echo "pwm discovery tests passed\n";