EdCole

When I bought my Cutlass 14 years ago, I was told that the man who had started restoring it (2 owners before me) had a stroke before he got to the dashboard and electrical systems. So it's always had a lot of electrical peculiarities, but most of them have been pretty easy to solve or work around if I keep trying things. I've been trying to get it back on the road after a 2 year hiatus, and noticed the brake lights and hazards are not working at all. I recently tore down the steering column to fix an ignition problem, and the brake light/hazard issue seems to have started after that. I read all the threads here on similar problems, but nothing recommended in those threads has worked for me.

The headlights, taillights, back-up lights, and all 4 turn signals work fine, which tells me it's not a bulb/socket problem. I replaced the brake light switch and hazard flasher. Turn signals stop working if the hazard switch is engaged. My circuit tester tells me I have continuity at the brake light switch, the plug for the taillight harness, and the brake light fuse (I noticed I had a blown brake light fuse and was sure that was the issue, but it wasn't. I replaced it and still, nothing). The hazard flasher plugs into the fuse box with those 2 prong slots at a 90 degree angle, and when I tested it with a circuit tester, one contact on each slot, it showed no continuity. I'm not sure if I was testing that correctly, but it seems to be the only place I can detect a possible problem.

Does anyone know if I'm testing the flasher slot in the fuse box correctly? Or what it might mean if I'm not getting any juice there? I thought it might also be a bad turn signal switch, but wouldn't that also cause problems with the turn signals themselves? I think I've pretty much reached the boundary of my limited expertise here.

matt69olds

Push and pull the hazard switch a few times. Sometimes that fixes screwy tail light issues. If not, I’m guessing your going to need to replace the turn signal switch. You can plug it into the harness to test it first.

joe_padavano

That is completely normal. The hazard button disconnects the turn signal flasher from the circuit and replaces it with the hazard flasher because the hazards use the same filaments in the 1157 bulbs. Also, stepping on the brake pedal when you have the hazard button pressed will cause the hazard lights to stop flashing and stay on all the time. I'm guessing that you've got a short somewhere that makes the hazard circuit think the brake pedal is pressed all the time. If you disconnect the plug from the brake light switch with the hazards engaged, do they flash?

Also, with everything else connected and the hazard button pressed, pull the hazard flasher out of the fuse panel and temporarily jumper across the two terminals in the panel. The turn signal filaments in the bulbs should all come on. Obviously they won't flash with the jumper in place. Also, with the jumper pulled out, the flasher module pulled out, but the hazard button pressed, no light should be on.

EdCole

I tried engaging flashers with the brake light switch disconnected, but no lights came on. Jumping the flasher terminal in the fuse panel with everything else connected and engaging the hazards switch also didn't work. I'm thinking what was said about the turn signal switch being bad might be correct, or possibly I messed something up when reassembling the steering column.

joe_padavano

That's about the only option left as a cause.

Vintage Chief

It appears it may or it may not be relative to the turn signal switch. However, can you and have you validated these tests with the IGN in the ON position and the IGN in the OFF position? Is there any difference? Reason, perhaps it's related to the prior fix you performed on the ignition problem inside the column?

joe_padavano

The brake light and hazard circuits are unrelated to the ignition switch - they are powered all the time. The only possible relationship to the ignition switch would be if the actuating rod in the column were somehow pushing on the wire harness from the turn signal switch.

Vintage Chief

There's no reason to suspect I know what the answer is here - only suggestions; but, doesn't the ORANGE wire run from the IGN SW into the HAZARD FLASHER and then into the STOP LAMP SW? Also, in that circuit, doesn't that ORANGE wire provide power to the HEATER/AC & BLOWER? If so, my next question would be does the HEATER/AC & BLOWER work with the IGN ON? Just asking....just asking. I thought the ORANGE power wire began inside the IGN SW but perhaps I'm incorrect on this. It should be hot all the time, but what if it is NOT hot right out of the IGN SW?

joe_padavano

No, it does not. The hazard flashers work with the ignition off or on. There is no connection between the hazard circuit and the ignition switch. Similarly, the brake lights work with the ignition off or on, and also there is no connection between the ignition switch and that circuit either. Both hazard and brake light circuits are powered from the aptly-named STOP-HAZ fuse, which in turn gets it's power from the junction post on the horn relay. If you are looking at the wiring diagram in the CSM and are looking at the orange wire from the ACC2 terminal on the ignition switch, that CROSSES OVER the orange wire to the hazard flasher, but does not connect to it. Convention in a schematic is to use a dot to show a connection in a four way splice. Without the dot, the schematic is simply showing a crossover. Look, for example, at the clock and courtesy lights in the lower RH corner of the wiring diagram. Note the black dot to show that the four way connection is a splice and not just a cross-over.

Vintage Chief

I was looking at exactly the point you have illustrated in the LH diagram above. However, it doesn't demonstrate ACC2 terminal, it demonstrates it only comes off the IGN STARTER SW. In any case, correct directly off the IGN SW. Honestly, sometimes it's a hit/miss deal for me with several of the wiring diagrams including the one on this website which is supposed to be from a 1971 A-Body and looks nothing of the type of wiring diagram from my 1971 CSM for an A Body "V-8". Point in case>>>1971 A body wiring diagram provided by Dfire25
That is NOT the 1971 Fig. 12-3 A Body "V-8" wiring diagram contained in my original 1971 CSM.

To your point though, I didn't realize your "Not a Splice" was a crossover I did believe it was a splice along the same circuit so that explains why I thought the ORANGE from the IGN SW fed that circuit.
I really don't mind reading wiring diagrams, and I'll tell ya, what one wiring diagram considers to be using known schematic convention sure doesn't always prove to be the case, IMO. Now I have to run down that white wire into that plug.

joe_padavano

Since the OP asked about a 1969, I'm looking at the 1969 wiring diagram, and in that CSM, the orange wire to the ignition switch is labeled ACC2. In any case, they are not connected electrically in either year.

joe_padavano

That's actually a 1968 wiring diagram. Of course, "free" information is worth exactly what you paid for it. This is why I have actually bought and paid for just about every year CSM. I don't consider the interwebs to be a reliable source of information - on ANY topic...

Vintage Chief

It should be either removed or the post should be titled correctly since it is NOT a 1971 wiring diagram.
So, I've reviewed your diagram and my 1971 CSM wiring diagram...and, note - with my large magnifying glass. And, I'll tell you, not all wiring diagrams were/are created equal. Where your diagram clearly demonstrates the fuse is connected to the orange wire, my diagram has a GAP the size of the Grand Canyon and it doesn't actually look like the fuse is even closely in contact with the orange wire....frustrating. Your diagram is far much better in that it is very crisp & clear. Mine is crisp & clear with a Grand Canyon gap between the fuse and the orange wire. Just this small stuff which can be a nuisance. Thanks for making the image, explaining and sharing. Always good to learn what's going on. Thanks again. I'm not going to take a picture of my CSM diagram, move it into the PC, create the image etc. Take my word for it!

joe_padavano

Yeah, the GM diagrams don't have the best quality control, and the registration of the various colors isn't always the greatest. There are a lot of places where the accuracy leaves a lot to be desired.

EdCole

A new turn signal switch did not fix the problem, and I have been trying each fix with the ignition in both the on and off positions. I think I need to get a 1969 chassis service manual or something with a wiring diagram to track down the issue here.

joe_padavano

Probably would have been my first choice...

Look, this is not a complex circuit.
1) Verify power at the terminal in the fuse box for the hazard flasher module.
2) Verify continuity in the brown wire from the hazard flasher socket to the turn signal connector on the steering column.
3) Jumper between the two terminals in the flasher socket on the fuse box and verify 12V at the brown wire.

If all that works, and the turn signals work, then the only POSSIBLE causes are a bad flasher or a bad turn signal switch, period. There are no other components in the system.

Vintage Chief

Regarding a bad flasher. You should be able to hear the flasher. If you cannot hear the flasher, well.....

EdCole

My circuit tester shows no continuity between the terminals for the hazard flasher in the fuse block. Also shows no current on either individual side of the terminal when I test with a ground outside of the fuse block. All other fuses show continuity. Brake light fuse (which I just replaced) shows 12v DC on one side, nothing on the other.
UPDATE: I just got everything to work. The brake fuse should have been showing continuity if it had current coming in and it was a brand new fuse. So I ... well I guess I wiggled it in its slot and it suddenly started working. I guess it was a bit corroded or something. Thank you everyone for your help and patience. Sorry for such an anticlimactic conclusion.

oldcutlass

Its funny that when this diagram was posted, no one noticed it until now... I change the title to reflect the correct info.

oldcutlass

Just an fyi, an ohm meter is not the best tool for checking continuity in linked circuits because of lamps, coils, etc... I prefer a test light or volt meter.

Vintage Chief

x2

Vintage Chief

Huh? It's working - celebrate.