6x6 - Why do the reversing lights not work when the hazard switch goes west?

[legless_hero]

The reversing lights do work, this problem only started when the indicators stopped working.

The hazard switch (it would seem) has gone to the big scrap yard in the sky in my '91 110 6x6 Cargo. The switch still works(for the hazards) but is seems to be stopping the indicators and reversing lights from working.

A few people have said it's the hazard switch and I found a tutorial on how to test the hazard switch on another site so I'm pretty certain that that is the problem.

What I don't understand is why the reversing lights don't work...

If I run a "raw" 12v to the oil pressure switch the lights work (engine running) so I assume that the issue is somewhere between the fuse and the oil pressure switch.

Looking at the circuit diagram I cannot see any inter-connection of the reversing lights, indicators or hazard swith except that the output from the fuse appears to feed the indicators and the reversing lights..... Ok so there is oen identifiable inter-connection. I've tested the fuse and it is ok (multi-meter/eyeball) burt there is nothing coming into the fuse so (obviousl) nothing going out.

Anyone think of a reasonable explanation?

Oh, I have a a new switch on order..but thanks to covid and his mates who knows how long it will take to get here...

Regards
Jon

[jillr]

Hi Jon,

I see you didn't get much of a reply to your question but I might hazard a guess. The Hazard light has to do three things: 1: Normal operation with no hazard; 2: Hazard operation disconnects normal light functions and 3: Hazard operation connects a flashing circuit to them.
My guess is the Hazard switch has collapsed internally so that it's stuck in feature 2 permanently and 3 only when Hazard is enabled manually.
The reason why it does not show up in the circuit diagram is most likely because the internals of the Hazard switch are not part of the serviceable parts. Generally one just replaces the faulty part. I guess you could pull it to bits and see what falls out but I am guessing you've got a new one and this is all just academic? [smilebigeye]
Cheers,

Jill

[p38arover]

Is this switch faulty?

Perentie 4BD1 Oil Pressure Switch, Reverse Light - KLR Automotive (https://klrautomotive.com.au/perentie-4bd1-oil-pressure-switch-reverse-light/)

I've been told it does fail.

The hazard light switch is readily available: Hazard Light Switch - KLR Automotive (https://klrautomotive.com.au/hazard-switch/)

[Blknight.aus]

to make fault finding a bugger.

[p38arover]

The oil pressure reverse light switch can be bypassed. I forget the reasoning behind its fitting, i.e., the engine must be running for the reverse lights to work.

[p38arover]

The oil pressure reverse light switch can be bypassed. I forget the reasoning behind its fitting, i.e., the engine must be running for the reverse lights to work.

I found out it's to stop the battery being drained if the vehicle is left in reverse with the engine off. The reversing lights aren't connected through the ignition switch.