diff --git a/src/lib/frp-engine.ts b/src/lib/frp-engine.ts
index 6ede5ca1..093d9e88 100644
--- a/src/lib/frp-engine.ts
+++ b/src/lib/frp-engine.ts
@@ -258,6 +258,17 @@ export class FrpEngine extends FrpVehicle {
         );
     }
 
+    /**
+     * Read suppression state from the brake pipe pressure. Requires a
+     * well-behaved air brake simulation that cuts out at 110 psi.
+     */
+    createBrakePressureSuppressionBehavior() {
+        return () => {
+            const psi = this.rv.GetControlValue("AirBrakePipePressurePSI") as number;
+            return psi <= 110 - 17;
+        };
+    }
+
     /**
      * Create a behavior for the speedometer speed.
      */
diff --git a/src/lib/shared/multilevel.ts b/src/lib/shared/multilevel.ts
index 0512e134..a3ded2e1 100644
--- a/src/lib/shared/multilevel.ts
+++ b/src/lib/shared/multilevel.ts
@@ -126,7 +126,11 @@ export function onInit(me: FrpEngine, version: Version) {
 
     // Safety systems and ADU
     const acknowledge = me.createAcknowledgeBehavior();
-    const suppression = () => (me.rv.GetControlValue("VirtualBrake") as number) > 0.5;
+    const suppression = frp.liftN(
+        (bp, lever) => bp || lever,
+        me.createBrakePressureSuppressionBehavior(),
+        () => (me.rv.GetControlValue("VirtualBrake") as number) > 0.5
+    );
     const speedoDigitsMph = me.createSpeedometerDigitsMphBehavior(3);
     const equipmentSpeedMps = (version === Version.Marc ? 125 : 100) * c.mph.toMps;
     const [aduState$, aduEvents$] = adu.create({
diff --git a/src/mod/Assets/DTG/ArrowIIIPack01/RailVehicles/Electric/Scripts/ArrowIII_Engine_Script.ts b/src/mod/Assets/DTG/ArrowIIIPack01/RailVehicles/Electric/Scripts/ArrowIII_Engine_Script.ts
index d118aab2..a0dadfa8 100644
--- a/src/mod/Assets/DTG/ArrowIIIPack01/RailVehicles/Electric/Scripts/ArrowIII_Engine_Script.ts
+++ b/src/mod/Assets/DTG/ArrowIIIPack01/RailVehicles/Electric/Scripts/ArrowIII_Engine_Script.ts
@@ -48,7 +48,11 @@ const me = new FrpEngine(() => {
 
     // Safety systems and ADU
     const acknowledge = me.createAcknowledgeBehavior();
-    const suppression = () => (me.rv.GetControlValue("VirtualBrake") as number) >= 0.5;
+    const suppression = frp.liftN(
+        (bp, lever) => bp || lever,
+        me.createBrakePressureSuppressionBehavior(),
+        () => (me.rv.GetControlValue("VirtualBrake") as number) >= 0.5
+    );
     const speedoDigitsMph = me.createSpeedometerDigitsMphBehavior(3);
     const [aduState$, aduEvents$] = adu.create({
         e: me,
diff --git a/src/mod/Assets/DTG/F40PH2Pack01/RailVehicles/Diesel/F40PH/CommonScripts/F40PH2_EngineScript.ts b/src/mod/Assets/DTG/F40PH2Pack01/RailVehicles/Diesel/F40PH/CommonScripts/F40PH2_EngineScript.ts
index 9e609051..e4de8701 100644
--- a/src/mod/Assets/DTG/F40PH2Pack01/RailVehicles/Diesel/F40PH/CommonScripts/F40PH2_EngineScript.ts
+++ b/src/mod/Assets/DTG/F40PH2Pack01/RailVehicles/Diesel/F40PH/CommonScripts/F40PH2_EngineScript.ts
@@ -56,7 +56,11 @@ const me = new FrpEngine(() => {
 
     // Safety systems and ADU
     const acknowledge = me.createAcknowledgeBehavior();
-    const suppression = () => (me.rv.GetControlValue("VirtualBrake") as number) >= 0.5;
+    const suppression = frp.liftN(
+        (bp, lever) => bp || lever,
+        me.createBrakePressureSuppressionBehavior(),
+        () => (me.rv.GetControlValue("VirtualBrake") as number) >= 0.5
+    );
     const [aduState$, aduEvents$] = adu.create({
         atc: cs.njTransitAtc,
         e: me,
diff --git a/src/mod/Assets/DTG/GP40PHPack01/RailVehicles/Diesel/GP40PH/Scripts/GP40_EngineScript.ts b/src/mod/Assets/DTG/GP40PHPack01/RailVehicles/Diesel/GP40PH/Scripts/GP40_EngineScript.ts
index baa74aef..88998feb 100644
--- a/src/mod/Assets/DTG/GP40PHPack01/RailVehicles/Diesel/GP40PH/Scripts/GP40_EngineScript.ts
+++ b/src/mod/Assets/DTG/GP40PHPack01/RailVehicles/Diesel/GP40PH/Scripts/GP40_EngineScript.ts
@@ -46,6 +46,9 @@ const me = new FrpEngine(() => {
 
     // Safety systems and ADU
     const acknowledge = me.createAcknowledgeBehavior();
+    // There's no suppression detent, so we'd ordinarily incorporate brake pipe
+    // pressure here, but that isn't a reliable indicator due to the cut out
+    // being 90 psi.
     const suppression = () => (me.rv.GetControlValue("VirtualBrake") as number) >= 0.5;
     const speedoDigitsMph = me.createSpeedometerDigitsMphBehavior(3);
     const [aduState$, aduEvents$] = adu.create({
diff --git a/src/mod/Assets/DTG/Morristown/RailVehicles/Passengers/Comet/Driving Trailer/Common Scripts/Comet_IV_Engine.ts b/src/mod/Assets/DTG/Morristown/RailVehicles/Passengers/Comet/Driving Trailer/Common Scripts/Comet_IV_Engine.ts
index 61be6e71..dfd42559 100644
--- a/src/mod/Assets/DTG/Morristown/RailVehicles/Passengers/Comet/Driving Trailer/Common Scripts/Comet_IV_Engine.ts	
+++ b/src/mod/Assets/DTG/Morristown/RailVehicles/Passengers/Comet/Driving Trailer/Common Scripts/Comet_IV_Engine.ts	
@@ -163,7 +163,11 @@ const me = new FrpEngine(() => {
 
     // Safety systems and ADU
     const acknowledge = me.createAcknowledgeBehavior();
-    const suppression = () => (me.rv.GetControlValue("VirtualBrake") as number) > 0.5;
+    const suppression = frp.liftN(
+        (bp, lever) => bp || lever,
+        me.createBrakePressureSuppressionBehavior(),
+        () => (me.rv.GetControlValue("VirtualBrake") as number) > 0.5
+    );
     const [aduState$, aduEvents$] = adu.create({
         e: me,
         acknowledge,
diff --git a/src/mod/Assets/DTG/NJT-Alp46/RailVehicles/Electric/Alp46/CommonScripts/Alp46_EngineScript.ts b/src/mod/Assets/DTG/NJT-Alp46/RailVehicles/Electric/Alp46/CommonScripts/Alp46_EngineScript.ts
index f72ecc99..5098312b 100644
--- a/src/mod/Assets/DTG/NJT-Alp46/RailVehicles/Electric/Alp46/CommonScripts/Alp46_EngineScript.ts
+++ b/src/mod/Assets/DTG/NJT-Alp46/RailVehicles/Electric/Alp46/CommonScripts/Alp46_EngineScript.ts
@@ -39,7 +39,11 @@ const me = new FrpEngine(() => {
 
     // Safety systems and ADU
     const acknowledge = me.createAcknowledgeBehavior();
-    const suppression = () => (me.rv.GetControlValue("VirtualBrake") as number) > 0.5;
+    const suppression = frp.liftN(
+        (bp, lever) => bp || lever,
+        me.createBrakePressureSuppressionBehavior(),
+        () => (me.rv.GetControlValue("VirtualBrake") as number) > 0.5
+    );
     const speedoDigitsMph = me.createSpeedometerDigitsMphBehavior(3);
     const [aduState$, aduEvents$] = adu.create({
         e: me,
diff --git a/src/mod/Assets/DTG/NorthJerseyCoast/RailVehicles/Diesel/ALP45DP/Scripts/ALP45DP_EngineScript.ts b/src/mod/Assets/DTG/NorthJerseyCoast/RailVehicles/Diesel/ALP45DP/Scripts/ALP45DP_EngineScript.ts
index 016687df..27055cf6 100644
--- a/src/mod/Assets/DTG/NorthJerseyCoast/RailVehicles/Diesel/ALP45DP/Scripts/ALP45DP_EngineScript.ts
+++ b/src/mod/Assets/DTG/NorthJerseyCoast/RailVehicles/Diesel/ALP45DP/Scripts/ALP45DP_EngineScript.ts
@@ -135,7 +135,11 @@ const me = new FrpEngine(() => {
 
     // Safety systems and ADU
     const acknowledge = me.createAcknowledgeBehavior();
-    const suppression = () => (me.rv.GetControlValue("VirtualBrake") as number) > 0.5;
+    const suppression = frp.liftN(
+        (bp, lever) => bp || lever,
+        me.createBrakePressureSuppressionBehavior(),
+        () => (me.rv.GetControlValue("VirtualBrake") as number) > 0.5
+    );
     const [aduState$, aduEvents$] = adu.create({
         atc: cs.njTransitAtc,
         e: me,
diff --git a/src/mod/Assets/DTG/NorthJerseyCoast/RailVehicles/Passengers/Comet/Driving Trailer/CommonScripts/CometCab_EngineScript.ts b/src/mod/Assets/DTG/NorthJerseyCoast/RailVehicles/Passengers/Comet/Driving Trailer/CommonScripts/CometCab_EngineScript.ts
index 8df5bc30..ee25a4b4 100644
--- a/src/mod/Assets/DTG/NorthJerseyCoast/RailVehicles/Passengers/Comet/Driving Trailer/CommonScripts/CometCab_EngineScript.ts	
+++ b/src/mod/Assets/DTG/NorthJerseyCoast/RailVehicles/Passengers/Comet/Driving Trailer/CommonScripts/CometCab_EngineScript.ts	
@@ -151,7 +151,11 @@ const me = new FrpEngine(() => {
 
     // Safety systems and ADU
     const acknowledge = me.createAcknowledgeBehavior();
-    const suppression = () => (me.rv.GetControlValue("VirtualBrake") as number) > 0.5;
+    const suppression = frp.liftN(
+        (bp, lever) => bp || lever,
+        me.createBrakePressureSuppressionBehavior(),
+        () => (me.rv.GetControlValue("VirtualBrake") as number) > 0.5
+    );
     const speedoDigitsMph = me.createSpeedometerDigitsMphBehavior(3);
     const [aduState$, aduEvents$] = adu.create({
         e: me,
diff --git a/src/mod/Assets/RSC/NorthEastCorridor/RailVehicles/Electric/AEM7/Default/Engine/RailVehicle_EngineScript.ts b/src/mod/Assets/RSC/NorthEastCorridor/RailVehicles/Electric/AEM7/Default/Engine/RailVehicle_EngineScript.ts
index 76e1a8fe..ca558069 100644
--- a/src/mod/Assets/RSC/NorthEastCorridor/RailVehicles/Electric/AEM7/Default/Engine/RailVehicle_EngineScript.ts
+++ b/src/mod/Assets/RSC/NorthEastCorridor/RailVehicles/Electric/AEM7/Default/Engine/RailVehicle_EngineScript.ts
@@ -30,7 +30,11 @@ const me = new FrpEngine(() => {
 
     // Safety systems and ADU
     const acknowledge = me.createAcknowledgeBehavior();
-    const suppression = () => (me.rv.GetControlValue("VirtualBrake") as number) >= 0.5;
+    const suppression = frp.liftN(
+        (bp, lever) => bp || lever,
+        me.createBrakePressureSuppressionBehavior(),
+        () => (me.rv.GetControlValue("VirtualBrake") as number) >= 0.5
+    );
     const [aduState$, aduEvents$] = adu.create({
         atc: cs.amtrakAtc,
         e: me,
diff --git a/src/mod/Assets/RSC/P32Pack01/RailVehicles/Passengers/Shoreliner/Driving Trailer/CommonScripts/CabCarEngineScript.ts b/src/mod/Assets/RSC/P32Pack01/RailVehicles/Passengers/Shoreliner/Driving Trailer/CommonScripts/CabCarEngineScript.ts
index 87171710..d05c3003 100644
--- a/src/mod/Assets/RSC/P32Pack01/RailVehicles/Passengers/Shoreliner/Driving Trailer/CommonScripts/CabCarEngineScript.ts	
+++ b/src/mod/Assets/RSC/P32Pack01/RailVehicles/Passengers/Shoreliner/Driving Trailer/CommonScripts/CabCarEngineScript.ts	
@@ -79,7 +79,11 @@ const me = new FrpEngine(() => {
 
     // Safety systems and ADU
     const acknowledge = me.createAcknowledgeBehavior();
-    const suppression = () => (me.rv.GetControlValue("TrainBrakeControl") as number) >= 0.4;
+    const suppression = frp.liftN(
+        (bp, lever) => bp || lever,
+        me.createBrakePressureSuppressionBehavior(),
+        () => (me.rv.GetControlValue("TrainBrakeControl") as number) >= 0.4
+    );
     const [aduState$, aduEvents$] = adu.create({
         atc: cs.metroNorthAtc,
         e: me,