AAaagghhh - still no brake lights or turn signals!!

[BT SNAKE]

Dan,
Which tail lights do you have ? The round ones or the single lens rectangle .
The only reason I ask is because I had similar issues with the rectangle ones. They use the Prince of Darkness bulb sockets and they SUCK ! I happen to see a superformance rear taillight assembly and knew that was the best way. Instead of buying theirs I just fabbed my own. I wanted better bulb sockets rather than those I had so I went to the U pick and found some really cool metal ones out of a 70's car. My problem went away. I know too you better have super good grounds with a glass car.
Don't mean to waste your time. I hope you find your issues and get back on the road.

Hersh

[DanEC]

I have the single bulb rectangular units. Thus the trailer relay that has to be used to allow the single bulb to handle tail light, brake light and turn signal functions.

Patrick - I'll check tomorrow but I think it's something other than the trailer relay. What would be the chances of having two relay that were identically faulty? There is something definately funky going on with the flasher unilt if you look at my voltage readings. Not sure it alone is enough to cause all of my problems.

[patrickt]

Remember the flasher unit "feeds" the turn signal switch. It becomes intermittent under load. You can jumper "across the flasher" and thereby deliver a constant 12v to your signal switch. If you do that, then signaling a turn will not flash the signal lights on the front and back of the car, but it should still light them (constantly, not flashing). I would definitely test your relays with clean input voltage. You know everything from the back lights to the relay works. Next step is test the relay, then test the signal switch, then test the flasher. That's all that's on the circuit -- you will have gone from nose to toes.

[BT SNAKE]

Dan,
I eliminated the trailer reg by doing the two bulb per side. That's what Superformance did too. So in the future you might want to try this approach.
I hope you find that miserable little bug and squash it. I'm with you on electrical stuff. I just hate it.

Good luck
Hersh

[DanEC]

Originally Posted by DanEC

What would be the chances of having two relay that were identically faulty?

To answer my rhetorical question - apparently the chances are pretty damn good of having two bad ones. Using 12V off of fuse 5 I can't get anything through the trailer relay - stone dead. I tried each wire - green, red, and yellow individually and nothing. I used my ohm meter on either side of the relay - completely open. I tried paring the red and yellow and red and green together and nothing - completely dead (yes, the ignition was on during all of this and the other side of the meter was grounded to a windshield frame bolt).

I then stabbed the fuse outputs to the rear lights again and each one lit up fine. I tried voltage through the old relay and did get partial voltage a couple times - it may be marginally better shape than the new one.

I soldiered the connections with the new relay and although I was watching the wire temp I may have induced too more heat on the relay than I expected. Guess I'll order another one from summit.

This is why I like mechanical points over electronic distributors.

[patrickt]

Tell you what... when the third relay comes, let's first bench test it on your work table with a 12v battery, two 12v brake light bulbs, and some wire. It'll only take five minutes to do that. OK?

[DanEC]

5 minutes sounds optimistic for me, but OK.

[DanEC]

Patrick - still awaiting the next shipment of trailer relays from Summit (this time I ordered two of them) but I did a little more testing.

I think I verified this before but when the brake is pressed I have power at the red wire entering the trailer relay. Applying 12V at the fuse connections to the rear lights gets me a brake light there. So brake light circuits are good from both ends to the relay.

I went back to the flasher unit - with ignition on, I get 12V at both the brown and yellow wires. Brown is power from down by the brake light switch and yellow feeds the turn signal switch. However, with my test light I get a bright bulb on the brown and a much weaker bulb on the yellow. I guess this is due to the flasher relay. It doesn't appear possbile to stimulate the flasher into activation by merely applying 12 power to it - not sure what that takes. I also tested the resistance between the yellow and brown leads and got 400 ohms, but again - I guess that has something to do with the flasher unit itself.

I next applied 12V power to the Y/R lead to the turn signal switch, and checked for power at the green and yellow wires leading to the fuses. On the left turn signal I got a lit test lamp on the left wire going to the trailer relay. On the right signal I got a lit test lamp on the right side wire going to the trailer relay. Neither L or R signal generated a bright bulb. This makes it appear the turn signals may be OK.

I also broke apart the original trailer relay and fooled around with it. Interestingly, it has a row or resistors/diodes/who know what else fed off of the red, yellow and green leads and not a one of them had any continuity across the legs. Every last one of them was dead as could be. I couldn't get an Ohm meter tone across any of them.

I'm beginning think that the 2A quick blow fuses are on the wrong side of the trailer relay. It looks like this thing needs some fused protection on the incoming sied rather than the outgoing circuits to the rear lights.

I haven't heard back any further from Bob. I hoped he might have some observation or suggestion based on his knowledge of the system.

Hopefully the new relays will be here Monday. I think I will install the next one without soldering the connections in case the heat from that is part of the problem.

[patrickt]

You can not check the flasher without putting a load on it, like two light bulbs. The load allows a little heating element inside the flasher to heat up, which then makes a piece of metal get hot and go "twaanggg" when it warps over and short circuits the heater element, causing it to cool down, and the piece of metal then contracts back to it's original position. The heater then does it again. That's how it turns the circuit to the bulbs on and off as that little piece of metal turns your lights on and off as it gets hot and cold.

The two fast blow fuses sit between the rear lights and the relay. The fuses under the hood sit between your battery and the relay. So, it's fused on both sides.

We will bench test your next relay on the kitchen table using a light bulb, some wire, and a battery. It will be easy to do.