diff --git a/RxSwift/Observables/Implementations/Timeout.swift b/RxSwift/Observables/Implementations/Timeout.swift
index ebf70c49..db210ca3 100644
--- a/RxSwift/Observables/Implementations/Timeout.swift
+++ b/RxSwift/Observables/Implementations/Timeout.swift
@@ -89,9 +89,7 @@ class TimeoutSink<ElementType, O: ObserverType where O.E == ElementType>: Sink<O
             }
             
             if timerWins {
-                if let other = self._parent._other {
-                    self._subscription.disposable = other.subscribeSafe(self.forwarder())
-                }
+                self._subscription.disposable = self._parent._other.subscribeSafe(self.forwarder())
             }
             
             return NopDisposable.instance
@@ -104,10 +102,10 @@ class Timeout<Element> : Producer<Element> {
     
     private let _source: Observable<Element>
     private let _dueTime: RxTimeInterval
-    private let _other: Observable<Element>?
+    private let _other: Observable<Element>
     private let _scheduler: SchedulerType
     
-    init(source: Observable<Element>, dueTime: RxTimeInterval, other: Observable<Element>?, scheduler: SchedulerType) {
+    init(source: Observable<Element>, dueTime: RxTimeInterval, other: Observable<Element>, scheduler: SchedulerType) {
         _source = source
         _dueTime = dueTime
         _other = other
diff --git a/RxSwift/Observables/Observable+Time.swift b/RxSwift/Observables/Observable+Time.swift
index dab8ef5e..30d6e504 100644
--- a/RxSwift/Observables/Observable+Time.swift
+++ b/RxSwift/Observables/Observable+Time.swift
@@ -354,13 +354,13 @@ extension ObservableType {
     @warn_unused_result(message="http://git.io/rxs.uo")
     public func timeout(dueTime: RxTimeInterval, scheduler: SchedulerType)
         -> Observable<E> {
-            return Timeout(source: self.asObservable(), dueTime: dueTime, other: nil, scheduler: scheduler)
+            return Timeout(source: self.asObservable(), dueTime: dueTime, other: Observable.error(RxError.Timeout), scheduler: scheduler)
     }
 
     @available(*, deprecated=2.0.0, message="Please use version with named scheduler parameter.")
     public func timeout(dueTime: RxTimeInterval, _ scheduler: SchedulerType)
         -> Observable<E> {
-            return Timeout(source: self.asObservable(), dueTime: dueTime, other: nil, scheduler: scheduler)
+            return Timeout(source: self.asObservable(), dueTime: dueTime, other: Observable.error(RxError.Timeout), scheduler: scheduler)
     }
     
     /**
diff --git a/Tests/RxSwiftTests/Tests/Observable+TimeTest.swift b/Tests/RxSwiftTests/Tests/Observable+TimeTest.swift
index a2ab447b..5c137f3b 100644
--- a/Tests/RxSwiftTests/Tests/Observable+TimeTest.swift
+++ b/Tests/RxSwiftTests/Tests/Observable+TimeTest.swift
@@ -1650,6 +1650,32 @@ extension ObservableTimeTest {
             Subscription(200, 270)
             ])
     }
+
+    func testTimeout_Duetime_Timeout() {
+        let scheduler = TestScheduler(initialClock: 0)
+
+        let xs = scheduler.createColdObservable([
+            next(10, 42),
+            next(20, 43),
+            next(50, 44),
+            next(60, 45),
+            completed(70)
+            ])
+
+        let res = scheduler.start {
+            xs.timeout(25, scheduler: scheduler)
+        }
+
+        XCTAssertEqual(res.events, [
+            next(210, 42),
+            next(220, 43),
+            error(245, RxError.Timeout)
+            ])
+
+        XCTAssertEqual(xs.subscriptions, [
+            Subscription(200, 245)
+            ])
+    }
     
     func testTimeout_Duetime_Disposed() {
         let scheduler = TestScheduler(initialClock: 0)