Welcome to Thursday Trivia where we offer up a historical automotive trivia question and you try and solve it before seeing the answer after the jump. It’s like a history test, with cars!
This week’s question: How did the sequential turn signals on the original Mercury Cougar work?
If you think you know the answer make the jump and see if you’re right.
Yesterday we went looking for Cougars of all stripes, and boy did you find some cool cats. You know, when it was introduced back in 1967 the Cougar was little more than a fancy Mustang. That was alright with everybody because who wouldn’t like a fancy Mustang? While sharing the basic Falcon-derived platform with its Ford cousin, the Cougar did not share any bodywork. Instead of the wide, gaping mouth of the Mustang, the new Cougar had a split grille with hidden lights and a prominent central prow.
In the back, Mercury’s cat further differentiated itself from the Mustang both in style and feature. Back where the Mustang had its by now iconic pair of three-segment tail lights, the Cougar had an amazing and futuristic band of lamps that would operate in sequence inside to out. This had previously appeared on the Thunderbird, but was the first time so fancy a feature would be used on a more plebeian ride.
It was an amazing feature and the most entertaining take on the turn signal since the trafficator, and people love fun stuff like that. In a nod to the past, and the passed, the current Ford Mustang adopts a sequential turn indicator for its traditional three-lamp units. That’s obviously operated today by one of the many computers the modern Mustang carries, but back when the feature first appeared on the Cougar (and Ford Thunderbird) it was via a far more mechanical method.
From Cougars Unlimited:
This article covers troubleshooting 1967-1968 Mercury Cougar sequential turn signals. While most the information has been acquired through experience on a 1968 model, the ideas can be applied when servicing a 1967 model too. This information is also applicable to 1967-early 1969 T-Birds as they share the same basic design.
The turn signal system has five electro-mechanical parts: the turn signal switch, (located in the steering column), a turn signal relay (located under the dash), a directional relay, an emergency relay, and a motor-driven sequencer (located in the driver’s side trunk under the mat or behind the backseat in T-Birds). The 1967 system also has an emergency relay and a turn indicator relay under the dash. The most failure prone parts are the mechanical sequencer, the turn signal switch, and the emergency relay in the trunk. Circuit diagrams may be found in the appropriate year factory shop manual.
Basically, the system works as follows: when the directional lever on the turn signal switch is moved, it completes circuits that select and feed power to the corresponding bank of lights. Power for the lights is fed through the turn signal relay to the sequencer. The sequencer has three cams that, when rotated, depress switches corresponding to the inboard, center, and outboard tail lights. The power is then routed first through the emergency relay (which disconnects all but the center light if the emergency switch is on for Cougars and connects all lights together for T-Birds.) and then to the directional relay. This two-sectioned (right and left) relay routes power through to the selected bank of lights. Since brake lights are not sequenced, the directional relay allows all lights to turn on simultaneously when the brake light power feed is energized. But when the turn signal switch is actuated, the brake light power feed is disconnected and the turn signal feed is activated to allow the directional signal to override the brake lights.
So there you go, a motor turns a shaft and cams complete connections. It’s wonderfully brilliant and Rube Goldberg at the same time. Today our cars are plumbed with computers and miles of wires all allowing us a multitude of modern features at our fingertips. It’s hard to remember back when that wasn’t the case, but as the Cougar’s wonderful tail lights prove, ingenuity always wins.