Short in hazard switch?

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BonitaCS

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Every time I turn on the turn signal or the hazard switch I blow fuse number 4. Done a lot of trouble shooting and think the culprit is the hazard switch. When I turn on the hazard switch pin 30 on the switch goes to ground, is this supposed to happen? It is the red wire with white stripes and is what supplies the power to the hazard switch. Any ideas?

Thanks,

Scott
 
Not the hazard switch

I've ruled out the hazard switch (I think)... I think it is the flasher unit. When I short red w/ white stripe (31) to the green & violet wire (49) the flasher doesn't turn on. I removed the flasher and teste it on the bench with 12V and nothing. So, if the flasher is not working could it cause the #4 fuse to blow when the hazard or turn signal is turne on? When I ohm out the flasher every pin is open to one another. At any rate I think the flasher is toast.

Scott
 
Scott,

A short in the unit could cause a fuse to blow...IIRC. I really would need a device map or current flow diagram to be sure or which pins to energize/test, but you are probably looking at the diagram on the unit. My wiring diagram is not with me right now.

I have had success removing relay covers and finding/cleaning contacts which had dust/debris in them...even had a coil inside which I could actually see the wire that fried (I merely reconnected and insulated) and fixed it.

Jon
 
flasher relay testing

You would have to place a load of at least two lamps on the relay to bench test. There is a bimetallic strip with points that heat up and cool down ( make and break.) but have to have a specific load 9.3a or less.

You have a short. Test each wire on the flasher , emergency, or stalk for ground with a resistance meter starting with the fuse terminal that blew- #4 and work your way up.

Don't have a meter-but extra fuses- pull the positive(s- Brown) from the device, new fuse, put them back on one at a time. You'll find it.
 
Was a short

While I haven't found the exact location it is definitely a short in the right hand turn signal (blue with black stripes wire). I'll try to isolate its exact location today and fix it, hopefully it is obvious. Interesting side note, while looking for the short I discovered my ohm meter will put enough of a load on the flasher unit to start it...

Thanks for your help!
 
loads that blow fuses

Tip: Substitute a test lamp for the blown fuse. A brake light bulb will work well. If the test lamp lights brightly, you have detected an excessive load without sacrificing another fuse.
 
For what its worth.

I found the short in the right front turn signal. As soon as I removed the turn signal assembly from the fender the short went away. It turns out there is a sheet metal grounding screw for the head lights and the turn signal which screws in from the head light side. I don't know if it is/was the original screw or a longer screw than the original one but it was sticking out long enough to make contact with crimp lug on the turn signal wire. The lug has a soft plastic isolating cover and, over time, it wore through the cover and was making direct contact with the lug. I drilled a new hole about an inch up and moved the grounding screw up so there will always be clearance regardless of screw length.

Scott
 
Well done!
A short, but not in the relay, a wire to ground...
...just like my 928, that due to the shorting of a couple of wires inside the wire harness, I re-wired the whole engine loom since NLA.
 
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