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Hazard wiring dilemma

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John_Mc

John_Mc

Jedi Knight
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My hazard lights don't flash and I'm trying to figure out why not. So using a voltmeter, I turned on the switch and checked the power to the hazard relay and I was able to get a reading of 12v so I checked the power into the flasher plug and I was able to get 12v. I checked the power OUT of the flasher plug and on one wire (LG/K) I was able to get 12v but on the other I got nothing. So I thought maybe my flasher was sticking. I took it out and banged it against the wall :hammer: and put it back in. No flashing lights. So I checked the above contacts again and now I was getting sporadic readings that seemed to settle at 2-3v. So I began to suspect the switch and I turned it off and on a couple of times. Now I get no voltage at any of the above spots. Again I'm suspecting the switch. However, switch or not, I would have thought that while I was getting the 12v readings, something would have lit up somewhere. Questions:

1. If it is the switch, how do I get it out to check it? (I've never removed the dash)
2. Is there anywhere I should check BEFORE the hazard switch?
3. Any other suggestions?
TIA
 
This is an odd circuit; in spite of the relay, the hazard switch has to carry the full current of all 4 turn/hazard bulbs.

From your description, I'm guessing you have multiple problems going on at the same time, which probably include a bad flasher and perhaps a bad switch. I would be tempted to try supplying 12v directly to the hazard relay (purple/red wire), and see if that makes them flash. That should put you back where you started, with the flasher apparently bad. Then when you get that working, you can worry about why the hazard switch is not supplying 12v to the relay (and lamps).

Er, the other purple circuit items are still working, right? Horns, interior lights, etc.? If not, I'd be looking at the fuse block where the purple circuit gets it's power.

Sorry, I can't help with how to get the switch out. From the drawing in the manual, I'd guess there are just two clips on the top & bottom of the switch that you compress, and push the switch out through the hole. But it doesn't look like there is room to reach those clips without pulling the dash forward. However, Mr Haynes suggests removing the cubby box lining (4 self-tapping screws) before removing any instruments, so perhaps that would let you get your arm in there to pop the switch loose.

Hopefully someone with a TR6 will be by soon, to tell how they did it.
 
Oops, waidda minit ... I misread your post. You said you found power on the LG/K wire from the flasher but not the LG/P. That might mean a dead flasher, but it might also mean the relay did not pull in or the lights are not connected to it. The hazard flasher has to see at least some current, or it won't flash.

So, put 12v on the relay (PR wire) as I suggested before, and then trace down why it's not getting to the lamps. If there's 12v on LG/K at the relay, but not GW and GR, the relay either isn't seeing 12v on it's coil (bad ground ?) or has failed.
 
Thanks Randall. I'll give that a try tomorrow.
 
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