no lights
Fleet Owner
Joined: Jun 1999
Posts: 24,552
Likes: 74
From: Creedmoor, North Carolina
The brake light and turn signal share the same filament in the bulb. The tail light uses the other filament.
You are gonna have to trouble shoot the issue. A circuit tester should have it working in about an hour or less. Remove the tail light bulb and start testing from there headed towards the cab.
John
You are gonna have to trouble shoot the issue. A circuit tester should have it working in about an hour or less. Remove the tail light bulb and start testing from there headed towards the cab.
John
Fleet Owner
Joined: Jun 1999
Posts: 24,552
Likes: 74
From: Creedmoor, North Carolina
Flashers can fail, it is a little can looking device a little bigger around that a quarter and about 1.25 in long. Bulbs can burn out, it is hard to say until you trouble shoot it.
Burned out bulbs will stop a flasher from flashing too. With the ign. switch on start with the brake lights get something weighted to hold the pedal down. Once you have working brake lights start attacking the flasher issue. They are pretty cheap, grab a new heavy duty one and replace it.
Bill can help with part numbers.
John
Burned out bulbs will stop a flasher from flashing too. With the ign. switch on start with the brake lights get something weighted to hold the pedal down. Once you have working brake lights start attacking the flasher issue. They are pretty cheap, grab a new heavy duty one and replace it.
Bill can help with part numbers.
John
Posting Guru
Joined: Feb 2007
Posts: 1,996
Likes: 9
From: Pittsburgh,Pa.
TC70, also check your fuses. These trucks use the same fuse for both stop lights and emergency flashers. A fuse could be blown or it could have corrosion in it's holder. The emergency flashers and turn signals have seperate flashers. 
Posting Guru
Joined: Feb 2007
Posts: 1,996
Likes: 9
From: Pittsburgh,Pa.
Flashers can fail, it is a little can looking device a little bigger around that a quarter and about 1.25 in long. Bulbs can burn out, it is hard to say until you trouble shoot it.
Burned out bulbs will stop a flasher from flashing too. With the ign. switch on start with the brake lights get something weighted to hold the pedal down. Once you have working brake lights start attacking the flasher issue. They are pretty cheap, grab a new heavy duty one and replace it.
Bill can help with part numbers.
John
Burned out bulbs will stop a flasher from flashing too. With the ign. switch on start with the brake lights get something weighted to hold the pedal down. Once you have working brake lights start attacking the flasher issue. They are pretty cheap, grab a new heavy duty one and replace it.
Bill can help with part numbers.
John
Industry standard part number for a 2 terminal flasher in these trucks is 552. It's likely been superceeded but a reasonably good parts person can interchange it pretty quick.
Senior User
Joined: Jul 2003
Posts: 290
Likes: 0
From: Las Vegas
Bulbs with corroded contacts and/or hairline cracks in the base can cause some very confusing issues like shorting the running light circuit to the turn signal/brake light circuit and some other symptoms. 1157 bulbs are cheap, so if I have an unusual problem, I typically replace both rear bulbs and then both fronts or at least remove all 4 before using my test light. YMMV.
Gene
Gene
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Fleet Owner
Joined: Jun 1999
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From: Creedmoor, North Carolina
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Senior User
Joined: Dec 2008
Posts: 266
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From: salt lake
tc70, you drive a ford you don't need working emergency flashers!lol!! my 67 doner truck was the same way. i could never figure it out, and all my lights worked under normal conditions (turn,park and brake)
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Posting Guru
Joined: Feb 2007
Posts: 1,996
Likes: 9
From: Pittsburgh,Pa.
Check the flasher. These trucks used seperate flashers for turn signals and emergency flashers. Most that I've seen had the emergency flasher mounted in a clip on the steering column brace. Look under ther dash on the right ( passenger ) side of the column. The reason they work with the signals is the power is back feeding thru the emergency switch.
Do the stop lights work?
Do the stop lights work?