diff --git a/gearslip/src/main/java/app/seb3thehacker/gearslip/ui/CertSetupScreen.kt b/gearslip/src/main/java/app/seb3thehacker/gearslip/ui/CertSetupScreen.kt
index f9c4302..f2b8698 100644
--- a/gearslip/src/main/java/app/seb3thehacker/gearslip/ui/CertSetupScreen.kt
+++ b/gearslip/src/main/java/app/seb3thehacker/gearslip/ui/CertSetupScreen.kt
@@ -107,6 +107,16 @@ fun CertSetupScreen(onDone: () -> Unit) {
                     fontWeight = FontWeight.SemiBold,
                     color = MaterialTheme.colorScheme.primary,
                 )
+                // A downloaded certificate works in most cars, not all: say where to go when it doesn't.
+                if (!manualProgress) {
+                    Text(
+                        stringResource(R.string.certsetup_installed_hint),
+                        style = MaterialTheme.typography.bodyMedium,
+                        textAlign = TextAlign.Center,
+                        color = MaterialTheme.colorScheme.onSurfaceVariant,
+                        modifier = Modifier.padding(top = 8.dp),
+                    )
+                }
                 Spacer(Modifier.height(20.dp))
                 Button(onClick = onDone, modifier = Modifier.fillMaxWidth().height(56.dp)) {
                     Text(stringResource(R.string.certsetup_continue))
diff --git a/gearslip/src/main/java/app/seb3thehacker/gearslip/ui/SettingsScreen.kt b/gearslip/src/main/java/app/seb3thehacker/gearslip/ui/SettingsScreen.kt
index 03f765d..e6d4e7d 100644
--- a/gearslip/src/main/java/app/seb3thehacker/gearslip/ui/SettingsScreen.kt
+++ b/gearslip/src/main/java/app/seb3thehacker/gearslip/ui/SettingsScreen.kt
@@ -255,7 +255,11 @@ private fun CertificateSection() {
         if (uri != null) pendingUri = uri
     }
 
-    SettingsSection(stringResource(R.string.settings_certificate), footer = notice ?: stringResource(R.string.cert_next_connection)) {
+    // With the aasdk certificate loaded, the footer says what to do when a car rejects it.
+    val certFooter = stringResource(
+        if (summary?.kind == CertProvider.Kind.DOWNLOADED) R.string.cert_downloaded_footer else R.string.cert_next_connection,
+    )
+    SettingsSection(stringResource(R.string.settings_certificate), footer = notice ?: certFooter) {
         val s = summary
         val loaded = s != null && s.kind != CertProvider.Kind.SELF_SIGNED
         val hasDetails = s?.subject != null || s?.issuer != null
diff --git a/gearslip/src/main/res/values/strings.xml b/gearslip/src/main/res/values/strings.xml
index 47c2306..3d874e7 100644
--- a/gearslip/src/main/res/values/strings.xml
+++ b/gearslip/src/main/res/values/strings.xml
@@ -125,9 +125,9 @@
     <string name="cert_download">Download from aasdk</string>
     <string name="cert_downloaded">Certificate downloaded.</string>
     <string name="cert_download_failed">Download failed: %1$s</string>
-    <string name="cert_download_sub">The certificate the open-source aasdk project publishes on GitHub. Gearslip doesn\'t include one</string>
+    <string name="cert_download_sub">The certificate the open-source aasdk project publishes on GitHub. Most cars accept it, but some from around 2020 on reject it</string>
     <string name="cert_import">Import my own file</string>
-    <string name="cert_import_sub">A .p12 file with its private key, from wherever you choose</string>
+    <string name="cert_import_sub">A .p12 file with its private key. Use your own when your car rejects the aasdk certificate</string>
     <string name="cert_remove_imported">Remove imported certificate</string>
     <string name="cert_remove_downloaded">Remove downloaded certificate</string>
     <string name="cert_removed_imported">Removed the imported certificate.</string>
@@ -330,13 +330,13 @@
     <string name="certsetup_continue">Continue</string>
     <string name="certsetup_failed">Download failed</string>
     <string name="certsetup_retry">Retry</string>
-    <string name="certsetup_import_sub">A .p12 file with its private key, from wherever you choose.</string>
+    <string name="certsetup_import_sub">A .p12 file with its private key. Use your own when your car rejects the aasdk certificate.</string>
     <string name="certsetup_skip">Skip car connection setup</string>
 
     <!--  -->
     <string name="certsetup_loaded">Cars accept only Google-issued certificates, and you have one loaded.</string>
     <string name="certsetup_choose">Cars accept only Google-issued certificates. Gearslip doesn\'t include one, so choose where yours comes from.</string>
-    <string name="certsetup_aasdk_sub">The open-source aasdk project publishes this certificate at github.com/opencardev/aasdk. Most cars accept it; some from around 2020 on don\'t.</string>
+    <string name="certsetup_aasdk_sub">The open-source aasdk project publishes this certificate at github.com/opencardev/aasdk. Most cars accept it. Some from around 2020 on reject it, and then you need to import your own.</string>
 
     <!-- Storage -->
     <string name="storage_title">Gearslip storage</string>
@@ -840,4 +840,10 @@
         <item quantity="one">%1$d meter</item>
         <item quantity="other">%1$d meters</item>
     </plurals>
+
+    <!--  -->
+    <string name="certsetup_installed_hint">If your car won\'t connect, it may reject this certificate. Import your own in Settings, under Certificate.</string>
+
+    <!--  -->
+    <string name="cert_downloaded_footer">Car won\'t connect? Some cars from around 2020 on reject the aasdk certificate, so import your own instead. Changes take effect on the next connection.</string>
 </resources>