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Tips
Tips

A bad brake/turn signal relay or ???

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Ed_K

Ed_K

Jedi Knight
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All of my turn signals and brake lights work. The dashboard turn signal indicators don't work. I have ohmed out the bulbs, the wires back to the terminal screws on the relay, the common wire back to the flasher, I replaced the flasher with an aftermarket, I took the relay cover off and burnished and aligned all of the contact points, still no dash indicators lights.
I noticed that when the left turn signal is flashing, if I touch the light socket case to ground the left indicator light starts working. I could not get the right indicator to work doing the same thing.
Perhaps the relative resistance of the turn signal lights and relay points are MUCH lower than the resistance of the indicator bulbs/wiring ??? Eventually
I will figure it out after I spend enough time/effort, but since I consumed most of the day troubleshooting this without any success has anyone seen this and what did you do to fix it ? Thanks for any ideas
 
Bob,
Thanks for responding.
On a BJ8, ( early wiring design with combined parking, turn signal, brake lights), the dash turn signal indicators appear to be grounded by the relay in the engine bay but only when the turn signal is in use. The wires go to the same terminal screws on the relay as the front turn signal lights. The front turn signal lights are working great, but not the dash indicator lights. This is why I am having difficulty figuring out what is wrong. The other common wire to the dash indicators goes to the center terminal of the turn signal flasher, the voltage as measured to ground is varying as expected during turn signal use but I cannot determine exactly how many volts is there because of the slow response from my inexpensive electronic multimeter.....
The only thing I can think of is to take the relay apart again, make a wiring diagram by mapping out all of the connections with an ohm meter, and then putting it back into the car without the cover. Then I can check/ test/ prod the relay while it is in use to see if I can figure out what is going on. I was hoping that someone else on the forum has already seen this bug and figured it out so I don't have to spend a lot more time on this. I'll also have to move the brake/clutch resevoir out of the way to do this. /ubbthreads/images/graemlins/crazyeyes.gif
 
I think I wasted a bunch of time on this problem because until now, I didn't open the shop manual, ( I don't need no stinkin book ! syndrome ). There is a good description of the operation of the flasher and trouble shooting on pages N14 and N15 of the shop manual. After reading this, I now know that I was " barking up the wrong tree " when I was checking out the relay. My problem must be on the 2ndary side of the flasher and I may just attach the pilot lamp wire to the wire that is on terminal L to see if the indicators start working.
 
The trouble shooting technique in the manual helped me isolate the problem. I tied all three wires together that feed the flasher. The indicator lights still did not light up but I was then able to check voltages and low and behold, I had 12 volts to ground on green/purple side of the lights. This meant it was not grounding through the relay. To make a long story short, one must have the front turn signal lights actually installed and connected to the car before one can expect the dash indicator lights to work, even though the rear turn signals were working with the front ones not yet reinstalled into the car ! I guess it needs the increased current to work the relay that the front lights being connected provides !
 
[ QUOTE ]
All of my turn signals and brake lights work. The dashboard turn signal indicators don't work. I have ohmed out the bulbs, the wires back to the terminal screws on the relay, the common wire back to the flasher, I replaced the flasher with an aftermarket....

[/ QUOTE ]Did this happen BEFORE you put in the aftermarket flasher unit? and do you have a good original Lucas flasher unit that you can try? I've heard that aftermarket flashers can cause this very problem, although I'm nowhere near enough of an EE to explain why. /ubbthreads/images/graemlins/confused.gif
 
Yes, It happened before I replaced the lucas flasher with the Stant 550. I have the front turn signals out of the car because I have not yet installed the three front wing to cowl ( shroud ) bolts on each side under the turn signal light holes in the body. I just finished a complete rewire of the car to add fuses into each circut. I was testing out everything when I discovered the turn signal indicator arrows were not working on the dash. At one point I did reconnect the front turn signals with them out of the car laying on the floor. They worked OK so I disconnected them again without checking if the dash indicators were working as a result of doing this. I didn't think they had anything to do with it at the time ! The stant 550 generic flasher ( $ 3.99 at Advanced auto parts ) works like a champ in my BJ8. After seeing how bright my turn signals and brake lights are now after burnishing the relay points, I would recommend that this be done once every ten years or so as preventive maintenance. I didn't have any problems with my wiring after adding 14 fuses to the car. This turn signal indicator " problem " was due to my ignorance of how the turn signal / brake relay works.
 
14 fuses, wow. I have added five, but wonder what the other nine are for. How about a list? It may be time to head back to radio shack for some more fuse holders.
 
I made two small panels and mounted them both to the heater plenum, one on the driver side and the other on the passenger side. On the drivers side I mounted two 5 position ATC/ATO fuse blocks. One the passenger side, I mounted one 5 position block plus two headlight relays that I bought from Victoria British as a set. On the drivers side I fused; overdrive relay, fuel pump, turn signal switch/ flasher, windshield wiper motor, fuel gage and tach electronics, brake light switch, heater blower motor, wire that loops behind tach then goes to coil, red wire off of light switch that feeds all parking lights, red wire off of light switch that feeds panel lights. On the passenger side, I put a 25 amp fuse in the wire that goes from the voltage regulator to the light switch, a 15 amp fuse to protect the input power to the headlight relays, and a 15 amp fuse to protect the cigar lighter. And last I added one two amp inline mini fuse to the red wire right before it exits the car for the license plate light bulbs. I have two empty positions on the passenger side fuse block for future use. I left the original lucas two position fuse block to protect the horn as original. And I jumperd the power to the other position to use it to feed the brown wire to the radio/stereo from the 2nd position. Perhaps a bit of overkill but If something happens, I'll know where to start looking for the problem. While
I was troubleshooting the flasher indicator lights, I accidently shorted the wire feeding the bulbs to ground and blew my turn signal/flahser fuse so it is protecting stuff already .
 
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