AAaagghhh - still no brake lights or turn signals!!

[DanEC]

!!@%#&$ - It wasn't the &*%#@@ trailer relay. Apparently that nearly severed connection at the trailer relay fuses was hanging on by a strand or two and there wasn't a problem with the relay. I installed another one and I have all the same issues - no brake lights with headlights off. Left brake light only with Lights on. left rear turn signal only with pressure on brake pedal.

More voltage checks

Flasher unit:

Left turn signal on: Brown 12.5V Yellow 2-9V flashing Blue .3-9V flashing

Right turn signal on: Brown 12V Yellow 6.3V steady Bule 0V

Power from Brake Light Switch - Pink wire under dash

Left turn signal on: 1.5 - 9V (with flasher)
Step on brake: 12 V steady with brake light in rear

Right turn signal on: 2.3V steady
Press on brake: 12 V but no brake light in rear

Turn Signal leads - I disconnected the two tan (brown) wires since they appear to only operate the headlight flashers. Disconnecting them didn't seem to change anything

Left turn signal on:
Blk/Gr to Green 1.5 - 8V flashing
Black to Yellow/Red 11.5V (I think this is power to the turn signal
Blk/White to Yellow 1.5 - 9V

Right turn signal on:
Blk/Gr to Green 6V
Black to Yellow/Red 11.5V
Blk/White to Yellow 6V

I don't know what to make of the above. It could be as simple as a bad flasher ( doesn't seem to be flashing on the rigtht side. It seems like on the right side it's just getting 6V from the flasher.

Could be the turn signal switch??

Could be both ???

Guess I'll try a new flasher since that is pretty cheap. Man, I hate electrical stuff.

[patrickt]

Disconnect the trailer side of the trailer relay and apply 12v to each of the two wires and see if the bright filament on each side of the rear of the car come on. Just use a jumper wire to feed the 12v.

[DanEC]

Originally Posted by patrickt

Disconnect the trailer side of the trailer relay and apply 12v to each of the two wires and see if the bright filament on each side of the rear of the car come on. Just use a jumper wire to feed the 12v.

Yes, both burn bright. Damn flasher unit must be Packard old stock or something. I went to three auto parts stores and none of them could match it up. Found one listing on EBAY. Google won't search for BUSS 180 - keeps changing it to Bus 180. Guess I'll have John at ERA send me one tomorrow. No driving this weekend.

[patrickt]

Originally Posted by DanEC

Yes, both burn bright. Damn flasher unit must be Packard old stock or something. I went to three auto parts stores and none of them could match it up. Found one listing on EBAY. Google won't search for BUSS 180 - keeps changing it to Bus 180. Guess I'll have John at ERA send me one tomorrow. No driving this weekend.

Test the relay(s) by disconnecting the three wires on the car side of the relay, hook up the two wires on the trailer side of the relay normally, then use a jumper wire to feed a clean 12v to each of the three leads to the relay. One should light one light, one should light the other light, and one should light both lights. If you get that far then you can combine the feeds to test it as if you have your foot on the brakes while signally a turn.

[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]

After reflecting some more on the wiring diagram I'm backing off on the turn signal flasher. It feeds the turn signal power through a common lead so there isn't any reason it would work in one direction and not the other. That leads me to the turn signal unit. I guess I will resume testing around it later today. Probably feed it 12V power as suggested and try switching the L and R rear light leads to see if the symptoms switch sides also

[patrickt]

Originally Posted by DanEC

After reflecting some more on the wiring diagram I'm backing off on the turn signal flasher. It feeds the turn signal power through a common lead so there isn't any reason it would work in one direction and not the other. That leads me to the turn signal unit. I guess I will resume testing around it later today. Probably feed it 12V power as suggested and try switching the L and R rear light leads to see if the symptoms switch sides also

No, don't test the relay by switching the left and right inputs. That might actually mask the true problem. You should test the relay by disconnecting the three inputs and by first applying a clean 12v to each of the two side inputs, then combining a side with a feed to the middle "brake light" feed. You see, the relay is just an "exclusive or" logic circuit. Kind of like the three way switches in your kitchen. Each rear light has two "inputs." One input is from the turn signal, the other from the brake light. If you have 12v coming from only ONE of these, the relay will light the bulb. But if you have 12v coming from BOTH inputs, the relay will not light the bulb. In a properly running system you can see this by turning the car on, then putting the left turn signal on. The green dash light and rear turn signal will flash in unison. They are both "in phase" with one another. But if you then push the brake pedal down, the flashing will switch out of phase. The rear turn light will flash when the green dash light is dark, and vice versa. So, do not test the relay by just switching the inputs (of which both may be faulty). You must use known-to-be-good, clean inputs, to test it.

[rodneym]

Maybe I was thinking of an isolating relay.

[DanEC]

I think it's more complicated than that. With the turn signal on and no braking, the only load is from the blinker element in the one bulb, plus what ever load contribution backfeeds from the front blinker element through the turn signal switch, plus the flasher unit.

While the flasher and front turn signal functions on a left signal, it's not functioning on a right signal - something is different on the right signal circuit versus the left one. I need to go back through all the connections on the right front parking/signal light and see if there is some reason for this. There is enough load to operate the flasher on the left side but not on the right side.

I also installed the panel over the master cylinders a couple months ago and wonder if I might have pinched a wire from the brake light circuit down there.

By the time I get this figured out I'm going to miss the spring season.

[patrickt]

Well, you'll be able to just plug in the new turn signal and flasher without doing a whole lot -- you don't have to actually put it on the column. It could always be the voltage leakage from the turn signal throwing off the circuitry. That would be nice.

[mickmate]

The trailer relays are what is used on a trailer behind American wiring that uses the brake light bulbs as indicators as well. They are simply diodes that only let electricity flow one way. Because the bulbs are used for both if you switch the indicator switch without diodes it also makes both the brakes work and flash. Are the diodes hooked for electricity to flow in the correct direction? They are like a one way valve.

[DanEC]

Originally Posted by mickmate

The trailer relays are what is used on a trailer behind American wiring that uses the brake light bulbs as indicators as well. They are simply diodes that only let electricity flow one way. Because the bulbs are used for both if you switch the indicator switch without diodes it also makes both the brakes work and flash. Are the diodes hooked for electricity to flow in the correct direction? They are like a one way valve.

Nick - as far as I can tell I've got it flowing in the right direction. There is a third wire coming in for power from the brake light switch and the relay is marked "To Vehicle" and "To Trailer" or something like that. There is also something going on with left side versus right side so I think I'm going to go back through all the signal light connections on the right side and see if I can figure out why the front signal light also isn't flashing over there. Maybe I have a loose ground at the front, loose connection or pinched wire somewhere.

[Jim Holden]

Have you checked all of the "pin" connections in the rear harness to be sure that the correct wire is feeding its correct counterpart?

It's extremely rare, but it wouldn't be the first time that ERA' Quality Control Supervisor missed a "crossed" wire...

Jim

[patrickt]

It should not be this hard. If you just put the relay on the kitchen table, attach 1157 bulbs to both of the output wires and the negative post of the battery, then feed 12v positive to the middle input wire (brake lights), the bulbs will light, unless the relay is bad. There is no tricky back feeding involved from the turn signals, no nothing -- you don't even have to hook them up. It's that simple for the first leg of the test -- you just leave the turn signal inputs alone, don't even hook them up.