Rear Hazard Flashers inop.

[Greggory2347]

1992 SL2, 150k.........noticed the other day during a 'walk around light inspection' that the rear 4 way hazard lights did not work, nor did the indicators on the dash. The front hazard lights work as they should.

The stop and turn signal lights work fine, as do the tail lights.

I also found out, that the directional blinkers will quit working for a few minutes after actuating the hazard lights, but they resume after what I assume is a cooling off/reset period on the circuit breaker.

So where do I start looking? Obviously the flasher is good, as evidenced by the front lights working. Anyone have a schematic? I have given the wiring a visual inspection but found no defect-I cannot imagine it being a fuse problem either so I have not checked them.

I am open to suggestions/ideas. Once again, it is a 1992 SL2 w/150k miles.
Thanks........

[RC1488]

Check all your fuses. The Hazard light relay is seperate from the directional relay. IIRC the Hazard one is in the underhood fuse box. See if you can find it and switch it with a simliar one. I dont have Factory service manuals to tell you exactly where it is. Sorry!

[Greggory2347]

Been there, done that. Sorry to say all that is good from what I can tell. Did I mention that the front lights [4 way] work as advertised? I have noticed that if I actuate the 4 ways, the normal directional blinkers will quit working for a few minutes. I think there is a short in the wiring going to the rear lights but not the front....just have not found it yet.

Thanks......

Originally Posted by RC1488

Check all your fuses. The Hazard light relay is seperate from the directional relay. IIRC the Hazard one is in the underhood fuse box. See if you can find it and switch it with a simliar one. I dont have Factory service manuals to tell you exactly where it is. Sorry!

[Ruley73]

Originally Posted by RC1488

Check all your fuses. The Hazard light relay is seperate from the directional relay. IIRC the Hazard one is in the underhood fuse box. See if you can find it and switch it with a simliar one. I dont have Factory service manuals to tell you exactly where it is. Sorry!

As far as I can tell, the hazard lights and turn signals have separate fuses/circuits, but both circuits use the same flasher located on the back of the interior fuse block. When the hazard switch is off the turn signal circuit (Turn Fuse 7.5A) is routed through the flasher and turn signal switch. When the hazard switch is turned on the turn signal circuit is bypassed and the hazard light circuit (Hazard Fuse 10A) is routed through the flasher and then the turn signal switch.

The hazard switch changes three circuits. It switches the turn signal circuit and hazard circuit (power feed) it switches on the front turn signal lights and rear turn signal lights on two different switches, but feeds them both from the same power source from the flasher so they all flash at the same time.

The turn signal switch has separate outputs for each turn signal light, but the indicator lights on the dash are powered by the output of the rear turn signal lights.

If you had a short somewhere, a fuse would have definitely popped by now so I don't think it's a wiring/short circuit issue. If the flasher is working intermittantly it may interfere with how your hazard lights and turn signals get power. I believe the symptoms you're experiencing that you think are from a circuit breaker are actually from a bad flasher (there are no circuit breakers for these circuits on your car). I would replace the flasher (Blazer p/n FL35, ~$10 from AutoZone). If a new flasher doesn't fix the problem, it must be in the turn signal/hazard combo switch. The latter isn't cheap, but don't fail very often in these cars.

[Greggory2347]

Thanks Ruley 73, you obviously have a schematic and know how to interpret it. This is the info I have been searching for prior to 'going in blind' and attempting to make sense of the readings I get.

I have suspected the 4 way flasher switch but not knowing much about how it is wired I have been reluctant to open the column for testing. I can proceed now with confidence, as soon as the weather co-operates with me. I will however first change out the flasher [I think I still have one from a parts car I bought/sold last year]-will also double check the fuses.

I will post what I find after I find it, just don't get in a hurry as this is my work car and need to have both the time and a warm place to troubleshoot the problem to conclusion.

[Greggory2347]

Update......fuses/good.....flasher/good......4way switch/????most likely suspect.

Will need to go to pick-a-part to get a different switch [and other nice to have parts]

Happy new year to all..............

[Ruley73]

Originally Posted by Greggory2347

Update......fuses/good.....flasher/good......4way switch/????most likely suspect.

Will need to go to pick-a-part to get a different switch [and other nice to have parts]

Happy new year to all..............

Make sure you get the right switch as there are a few variants. W/airbag, W/O airbag + W/cruise, and W/O airbag + W/O cruise. Each combination of these options uses a different turn signal/hazard combo switch.

You can find a used one by going to www.car-part.com and looking under "Column Switch".

Good Luck