tail lights always on

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Jan 23, 2012 | 11:10 PM

bubba_3711

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tail lights always on

i have A 1985 f150 step side and anytime the key is turned over my tail lights are on. i thought maybe the wire that grounds the bed to the frame? havent tryed anything yet. anyone have any ideas?

Jan 24, 2012 | 02:01 AM

Ranger80

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From: Owensboro, KY

It doesn't really make sense for them to only be on when the key is turned on, are they ever on while the key is off? The tail lamps as well as the brake lamps operate independently of the ignition switch, which leads me to believe maybe your turn signal circuit is somehow bleeding current to the bulbs while the key is on. Do your turn signals function normally? I'm no expert in this field by any means, so hopefully somebody more knowledgeable will chime in as well.

Jan 24, 2012 | 08:03 AM

lavatan

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From: Rock Valley, IA

It may seem crazy but have you checked your brake pedal switch? If, for whatever reason, it is not touching that will cause the brake lights to be on all the time.

Jan 24, 2012 | 09:39 AM

ctubutis

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From: Denver Metro Area, CO

The rear bulbs have two filaments and are fed by different circuits.

- The tail lamps, which come on when the headlight switch is pulled out at least halfway

- The stop lamps, which are activated by the brake pedal, turn signal lever, and emergency flasher switch

My guess would be a problem in the turn signal switch but you need to investigate and determine which circuit has the problem.

Jan 24, 2012 | 04:18 PM

bubba_3711

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well one day when it was about -60 i turned my turn signal on and somthing in side broke so only the left blinker works now, and when i turn on the right one the blinker stays on and doesnt blink. so it probally is my blinker switch.

Jan 24, 2012 | 04:32 PM

ctubutis

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From: Denver Metro Area, CO

Probably the TS switch cam, take off the steering wheel to investigate (but mark its location so it can be put back on exactly where it was).

New cams can be gotten from the HELP! section of auto parts stores but they don't have a real good record out here for longevity.

Jan 24, 2012 | 04:40 PM

81-F-150-Explorer

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From: Northern California

I'd replace the turnsignal switch, the brakelamps go through the switch and it sounds like its busted inside and connecting circuts improperly from your description.

Edit: the blinker staying lit and not flashing can be a short circut, or a bulb being burned out somewhere. on the side effected.