Guest dwhiteside64 Posted June 17, 2013 Share Posted June 17, 2013 (edited) Hi,I am in the process of troubleshooting a dim brake light. I already checked the bulb socket, cleaned it and made sure a new bulb was placed properly in the socket. The other tail light works correctly. From what I can ascertain, I think the problem is in the turn signal circuit mounted in the steering column. Here is how I believe the circuit(s) work:1) The same filament of dual filament light bulb is used for both stop and turn signal lights (1157). The second filament of this light bulb is used for the tail lights when the dash light switch is pulled out.2) With the turn signal lever in neutral position(center,) the stop light switch mounted on brake pedal will close the circuit to the brake lights and turn them on. This circuit electrically still travels through the turn signal lever circuit assembly mounted in the control column, which completes the signal to the brake lights.3) When the turn signal lever is engaged up or down, the flasher unit (mounted on the fuse block) becomes part of the circuit,and this signal travels to the stop light/turn signal light bulb filament allowing it to blink. During this time, the stop light switch on the brake pedal assembly has no control of the brake light on that side of the vehicle (although it will still effect the other tail light). If anyone has troubleshot a similar problem or believes I have the operation wrong, please let me know. Thanks! Edited June 17, 2013 by dwhiteside64 (see edit history) Link to comment Share on other sites More sharing options...
68RIVGS Posted June 17, 2013 Share Posted June 17, 2013 Make certain the dim tail light housing has a good chassis ground. Dim or non functioning bulbs are often just the result of a poor, or corroded ground connections.Just run an additional ground wire to the unit housing to see if this solves the problem. Link to comment Share on other sites More sharing options...
Guest dwhiteside64 Posted June 17, 2013 Share Posted June 17, 2013 OK I will try this, but both my tail lights are bright when using the dash light switch. Wouldn't this mean that the ground is good, as both filaments in the bulb use the same ground? Link to comment Share on other sites More sharing options...
RivNut Posted June 17, 2013 Share Posted June 17, 2013 Good question. Does the dim brake light bulb brighten up when used as a turn signal? If so, you could have some corrosion in the turn signal switch located on the steering column under the dash. Link to comment Share on other sites More sharing options...
68RIVGS Posted June 18, 2013 Share Posted June 18, 2013 . . . try replacing the old flasher with another working flasher unit ??? Link to comment Share on other sites More sharing options...
Guest dwhiteside64 Posted June 18, 2013 Share Posted June 18, 2013 I will look at the turn signal brightness. I have thought about replacing the flasher unit as well (or maybe just re-seating it). Thanks guys. Link to comment Share on other sites More sharing options...
Guest dwhiteside64 Posted July 8, 2013 Share Posted July 8, 2013 (edited) Hi everyone,Well, I went through the wiring this weekend and found loose grounds on BOTH tail light sockets - thanks Randy. Now my turn signals work, along with the parking lights. The only lingering problem is with my right brake light (it doesn't light at all). My left work just fine. After looking at the schematics, it looks like the problem is inside the turn signal switch that is mounted at the base of the steering column. One of the contacts is bad (that is used with the the turn signal lever in the neutral posistion). Does anyone know of a good replacement switch part number and source? I have tilt steering, so that may be important when selecting the right switch. Thanks,Darren Edited July 8, 2013 by dwhiteside64 (see edit history) Link to comment Share on other sites More sharing options...
Jim Cannon Posted July 9, 2013 Share Posted July 9, 2013 Darren-The problem is probably not the switch. It is probably the actuating cable from the turn signal lever in the steering column "head" down to the switch. See if the housing is broken. Link to comment Share on other sites More sharing options...
Guest dwhiteside64 Posted July 9, 2013 Share Posted July 9, 2013 Darren-The problem is probably not the switch. It is probably the actuating cable from the turn signal lever in the steering column "head" down to the switch. See if the housing is broken.Hi Jim,Are you saying that the neutral position of the switch could be incorrect? I suspect that when the turn signal lever in the center, the switch should also be physically in the center as well (this should allow for brake lights to work). I do think there is a problem with the cable, as the tilt wheel location effects the physical movement of the switch, and this is not correct. Should I see this cable easily after removing the steering column mast jacket?Darren Link to comment Share on other sites More sharing options...
1965rivgs Posted July 9, 2013 Share Posted July 9, 2013 Darren, Sounds like you are on the right track. To confirm that the position of the switch is causing your brake light issue manipulate the tilt thru its range of motion while having someone watch the malfunctioning brake light. At some point in the range of motion the switch should settle in the neutral position (the position it would remain in if the cable casing was intact) and the light should function. Wise to do this quick check before tearing into the steering column. Good luck, Tom MooneyPS A little harder but you could also use a jumper wire at the switch to check the circuit from the switch back to the light. Link to comment Share on other sites More sharing options...
Guest dwhiteside64 Posted July 9, 2013 Share Posted July 9, 2013 Thanks Tom that's real good advise. I will see how it behaves when I do this and get back to you.Darren Link to comment Share on other sites More sharing options...
Guest dwhiteside64 Posted August 21, 2013 Share Posted August 21, 2013 Hi all - just want to thank everyone for the advice. I got the brake lights to work, and the turn signals function as expected. I think it was a combination of problems (sockets, corrosion on turn signal switch, and tilt wheel). I still have a problem when using the tilt wheel (lights only work with wheel in certain position, but it's comforting to know that people can see when I am trying to stop lol! I will tackle the tilt wheel issue at a later date. Link to comment Share on other sites More sharing options...
RivNut Posted August 21, 2013 Share Posted August 21, 2013 The tilt wheel problem comes from a broken cable housing. If/when you find a fix, let everyone else know; you'll become an instant hero. Has anyone used the LED replacement bulbs in the OE sockets for more intense lighting? Ed Link to comment Share on other sites More sharing options...
Rocket 88 Posted April 3, 2015 Share Posted April 3, 2015 I had bought a pair of 1157 LED bulbs thinking they would be much brighter. I am guessing there were about 12 red led bulbs on this unit. installed one on the left tail light, and left a regular clear 1157 on the right. I see no difference in brightness, so I am using the reg. OEM 1157 bulbs.rocket88 Link to comment Share on other sites More sharing options...
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