Number 11 fuse keeps blowing (indicator lights)

[avant-garde]

Hi, I have a 1982 2.0 T25 Aircooled and I have just had a new gearbox fitted. Drove back from the garage this morning and there are no indicators. The green light on the dash stays on when the indicator is used.

I've replaced the number 11 fuse 3 times and every time it has blown immediately.

The hazard lights work no problems.

Does anyone have any idea how I go about tracing the fault? I'm assuming that there is a short somewhere. Do you think the new gearbox has anything to do with the blown fuse as it was working fine before the new gearbox was fitted.

I appreciate any help and advice that you can give me.

Many thanks,
Kevin

[avant-garde]

As soon as I turn the ignition on 1 click before cranking the fuse blows.

I have no idea what to do?

Any ideas would be helpful

[MidLifeCrisis]

Does the fuse only blow if you move the indicator stalk (i.e. if you indicate left or right)?

[avant-garde]

I thought so at first with my first three fuses that operating the indicator stalk blew the fuse...just tried another new fuse and as soon as I turned the key the fuse blew. The stork was not on.

I have no idea what to do.

[MidLifeCrisis]

If the Hazard warning light switch still flashes the lights correctly (when the indicator fuse has blown) - then the problem must be between the blown fuse and the hazard warning light switch (Haynes sayes there should be a black/blue wire running from that fuse to pin 15 on the Hazard switch - so somewhere between the blown fuse and the hazard warning light switch (pin 15) there is a short to ground.

Does that make sense?

[avant-garde]

Yes that makes perfect sense. I'll have a look tomorrow. Many thanks for your help

[avant-garde]

If the Hazard warning light switch still flashes the lights correctly (when the indicator fuse has blown) - then the problem must be between the blown fuse and the hazard warning light switch (Haynes sayes there should be a black/blue wire running from that fuse to pin 15 on the Hazard switch - so somewhere between the blown fuse and the hazard warning light switch (pin 15) there is a short to ground.

Does that make sense?

So to test that would I be right in saying the following:

So if I were to pull the black/blue wire out of the hazard warning light switch and pull the other end of the same black/blue wire out of the fuse box at N0. 11 and then run a new wire from No.11 fuse box to the hazard warning light switch ...that should then make the indicators work? Am i right in saying that?

In other words the short must be behind the dashboard somewhere between the hazard light switch and the fuse box.

[MidLifeCrisis]

Yes - that would be my guess.
The only slight variation on that is that it could be something inside the hazard switch (i.e. something in the switch has busted and is earthing that wire internally) or even less likely it could be something right at the fuse (possibly a small piece of wire or something is shorting out the fuse).

You might try just disconnecting the hazard switch from its plug and switching the ignition on - see what that does - if it doesn't blow the fuse then its probably something in the switch. If it does blow then its probably in the wire, then disconnect the wire from the fuse and repeat ..... hope you've still got a few fuses left

Good luck

[avant-garde]

MidLifeCrisis your advice and wisdom did the trick.

I took the blue/black cable of the hazard switch and a different blue/black cable off the fuse box...then ran a test cable from the fuse to the hazard switch and all works fine.

The thing I can't get my head round is that there are two black/blue cables coming out of the fuse box - 1 goes to the hazard switch the other disappears out the front bulkhead...what I don't understand is that the flashers only work when the blue/black wire from the fuse box to the hazard is disconnected at the hazard end and the blue/black wire going out of the bulkhead is disconnected at the fuse box.

So wouldn't that mean that there are two black/blue cables not connected at one of their ends?

Oh well who knows, at least the flashers work now.

Once again many thanks for your help.

[MidLifeCrisis]

........The thing I can't get my head round is that there are two black/blue cables coming out of the fuse box - 1 goes to the hazard switch the other disappears out the front bulkhead...what I don't understand is that the flashers only work when the blue/black wire from the fuse box to the hazard is disconnected at the hazard end and the blue/black wire going out of the bulkhead is disconnected at the fuse box...........

Glad its all working but you might want to try to figure out what that 'strange-ness' is cos the only black/blue I can find is one that powers the reverse lights?!? (You might want to check that your reverse lights are working)

Are you saying that the number 11 fuse has two black/blue wires coming off it? Or is the other black/blue off a different fuse?

Ah - this might all start to make sense now regarding your new gearbox ...... consider this scenario
a) if your reverse light circuit is incorrectly attached to the number 11 fuse (I think it should be attached to the number 12 fuse)
b) and the reverse light switch on the gearbox is shorting to ground (perhaps because it has been installed incorrectly)
Then that could be what is blowing the number 11 fuse?

Try this:
1) Leave everything as you had it set, i.e. both of those black/blue wires with one end disconnected and your test cable added so that the indicators work.
2) Check if your reverse light(s) are working (with the ignition on obviously)
3) If they are not working, try reconnecting the black/blue wire to the hazard switch (and remove the test cable you added) - see if your indicators are now working OK (again you'll need the ignition on). Hopefully they will now work (because that cable was never the problem).
4) Now put the other black/blue wire (the one that we now suspect may be the reverse light wire) back onto the number 12 fuse (note that's the number 12 fuse), turn the ignition on and the number 12 fuse should now blow (but obviously the indicators will now continue to work).
5) If number 12 fuse has now blown then you have tracked the problem down to the reverse light circuit and the obvious suspect has to be the reverse light switch on the gearbox (given that you've just had the gearbox messed with).

Make sense? (-ish)