no brake lights
Lead Driver
Joined: Nov 2006
Posts: 5,217
Likes: 506
From: Pa.
Yes that's what the diagram shows . Have you checked out the flasher relay? just bypass the brake switch for test purposes by unplugging both leads and clipping them together .. The brake lights should work ..
Posting Guru
Joined: Sep 2009
Posts: 1,159
Likes: 1
From: Suburbs of Chicago
Okay, whole new ballgame now. Everything is plugged in right?
Red lead at red wire going into BOO switch, black lead at shiny metal. You should have 12v. Do you?
Red lead at red wire going into BOO switch, black lead at RED/BLK coming out. 0v when pressing pedal, or 12v?
0v = okay, 12v= bad switch, make sure its in adjustment before condemning
Red lead at red wire going into BOO switch, black lead at shiny metal. You should have 12v. Do you?
Red lead at red wire going into BOO switch, black lead at RED/BLK coming out. 0v when pressing pedal, or 12v?
0v = okay, 12v= bad switch, make sure its in adjustment before condemning
Lead Driver
Joined: Nov 2006
Posts: 5,217
Likes: 506
From: Pa.
Look at the plug in lay out to see if they match and then look at the IDs to see if they are rated the same
Lead Driver
Joined: Nov 2006
Posts: 5,217
Likes: 506
From: Pa.
so unplug the leads from brake switch and touch them together if you have a helper at rear of truck .. otherwise alligator clip them and check brake lights yourself .. if this fails try again with unpluged Hazard relay
Posting Guru
Joined: Sep 2009
Posts: 1,159
Likes: 1
From: Suburbs of Chicago
Not a big deal.
I'm assuming you had the leads as I told you, double check that.
We now know the brake switch is OK.
With red lead at RED/BLK at TSS, black lead at shiny metal with pedal depressed do you have 12v or 0v?
With red lead at WHT/RED at TSS, black lead at shiny metal with hazards on, do you have 12v or 0v?
If you have 12v at both of these, time to move on with diagnosing the TSS and read below. If not, we have a open somewhere earlier in the wiring.
With red lead at GRN or YEL/BLK at TSS (test both), black lead at shiny metal do you have 12v with pedal depressed?
With red lead at GRN or YEL/BLK at TSS (test both), black lead at shiny metal do you have 12v with hazards on?
I'm assuming you had the leads as I told you, double check that.
We now know the brake switch is OK.
With red lead at RED/BLK at TSS, black lead at shiny metal with pedal depressed do you have 12v or 0v?
With red lead at WHT/RED at TSS, black lead at shiny metal with hazards on, do you have 12v or 0v?
If you have 12v at both of these, time to move on with diagnosing the TSS and read below. If not, we have a open somewhere earlier in the wiring.
With red lead at GRN or YEL/BLK at TSS (test both), black lead at shiny metal do you have 12v with pedal depressed?
With red lead at GRN or YEL/BLK at TSS (test both), black lead at shiny metal do you have 12v with hazards on?
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Posting Guru
Joined: Sep 2009
Posts: 1,159
Likes: 1
From: Suburbs of Chicago
Did you touch your meter lead to the metal of the connector? Or, if you are poking a wire, are you sure you made contact with a conductor in the wire?
I find it very weird that neither input works, double check you are making good contact with your meter lead with whatever you are testing.
I find it very weird that neither input works, double check you are making good contact with your meter lead with whatever you are testing.
Thread Starter
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Senior User
Joined: Dec 2004
Posts: 438
Likes: 0
From: Palm Bay,Florida
I have no 12v at red/black wire at tss. EDIT no power with pedal pressed
I have 12v at white/red wire at tss with hassard switch OFF but 0 volts with switch ON.
No speed control.
I have 12v at white/red wire at tss with hassard switch OFF but 0 volts with switch ON.
No speed control.