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Argh help! Hazard issues
Norfolkluegojnr - 13/4/16 at 06:02 PM

So my hazards don't work.

First of all, indicators work fine. I've changed the switch and the relay to no avail.

When the switch is on it just buzzes, then eventually stops. I've checked the power to the switch which is fine. Earth seems ok too. Checked Earth on the relay, seems fine.

Nothing else obviously amiss. It's the only thing needed for MOT and I'm totally stuck.

Any ideas?

Edit: to add I'm using escort mk2 loom, so single flasher unit for indicators and hazards.

[Edited on 13/4/16 by Norfolkluegojnr]


gremlin1234 - 13/4/16 at 06:57 PM

two questions,
have they ever worked?
and
are you using led bulbs?


Norfolkluegojnr - 13/4/16 at 07:17 PM

Yes they have worked I believe, certainly passed mot before.

No, just normal bulbs.


loggyboy - 13/4/16 at 07:26 PM

Are there separate relays for normal indicators and hazards?

All earths and connectors clean?


Norfolkluegojnr - 13/4/16 at 07:29 PM

It only has one relay. Works hazards and indicators.

I've chased the wiring and can't find anything obviously wrong. It's driving me nuts!


Dusty - 13/4/16 at 08:49 PM

There are two power supplies for driving the relay. 'Ignition on' supply for indicators. 'Battery+' for hazards. Sounds like you have a supply problem for the bat+. Trace it from fuse to hazard switch and check the hazard switch contacts too.

[Edited on 13/4/16 by Dusty]


snowy2 - 14/4/16 at 06:45 AM

hazard switches are often the problem, next the relays.......


Norfolkluegojnr - 14/4/16 at 06:52 AM

Switch has been replaced, as has relay. Good 12.4v at relay, earth seems fine too.

Could it be the indicator stalk?


theprisioner - 14/4/16 at 09:12 AM

There are two types of hazard relays the dual type (does hazards and indicators): as the man above says needs a dual supply switched as well as fixed 12v. And the dual relay configuration. CBS catalogue does a very good description of both ccts. My money would be on the hazard switch if you have the correct relay fitted.


Norfolkluegojnr - 14/4/16 at 09:43 AM

Thanks for the input - switch replaced, relay replaced. Both items are direct replacements with matching part numbers.

As the feed wire runs through the indicator arm, is it possible this messing with the signal? indicators work, but its the last thing I can think of. I'm 99% sure all wiring is fine from switch and relay.


theprisioner - 14/4/16 at 09:55 AM

These hazard ccts sort of tell you what is wrong. When in hadard mode the indicator switch should have no effect. In either mode the number of bulbs drawing current dictate the flash rate. If in normal mode then if you remove a bulb it should flash faster. In hazard mode the same applies. The hazard (dual relay) has two mode the high current mode and the low current mode dictated by the load. If in hazard mode you lose a bulb it may revert to low current mode or somewhere in between I guess.


Norfolkluegojnr - 14/4/16 at 10:09 AM

quote:
Originally posted by theprisioner
These hazard ccts sort of tell you what is wrong. When in hadard mode the indicator switch should have no effect. In either mode the number of bulbs drawing current dictate the flash rate. If in normal mode then if you remove a bulb it should flash faster. In hazard mode the same applies. The hazard (dual relay) has two mode the high current mode and the low current mode dictated by the load. If in hazard mode you lose a bulb it may revert to low current mode or somewhere in between I guess.


Hazard has no effect when indicators are on, and vice versa.

so are you suggesting to try pulling a bulb out to see what happens?

Does the circuit earth anywhere other than at the relay?


theprisioner - 14/4/16 at 02:32 PM

Well I assume that 4 bulbs illuminate in flash mode and only two in indicator mode. Yes remove a bulb and see what happens. It should go faster. in either mode.


Norfolkluegojnr - 14/4/16 at 02:37 PM

quote:
Originally posted by theprisioner
Well I assume that 4 bulbs illuminate in flash mode and only two in indicator mode. Yes remove a bulb and see what happens. It should go faster. in either mode.


I'll give it a try and report back.

Currently, nothing happens (other than a bit of buzzing) when hazard mode is engaged. it feels like an earth issue, but i've checked that and it seems to be earthing fine.


theprisioner - 14/4/16 at 03:35 PM

Idea

Stage 1: Take two bulbs 21W each connect them in parallel with the flasher unit in series (no other car wiring at all) then connect the whole lot across a 12V battery. If it does not flash then the flasher is effective otherwise you have a simple wiring fault.

Stage 2: remove the flasher switch the indicators should work without it provided you link the flasher to the wiper part of the indicator switch. Then the only thing left is the hazard switch.


snowy2 - 16/4/16 at 07:30 AM

This the wiring for a conventional hazard switch (they have 8 pins but with two blanked off....generally)

[img][/img]

[Edited on 16/4/16 by snowy2]