TR7 & TR8 Forum

I am trying to track down a few electrical problems. At this point I have no turn signals, hazard light or brake lights. When I got the car all of the relays connected to the fuse box were hanging loose. I am pretty sure I have 3 of the 4 back on, I am waiting for the other headlight relay to connect the 4th. I have 2 wires on the left, a purple and a green and I see 2 lugs on the left of the FB. Any idea which goes on top? i'd like to get that back on and proceed with trouble shooting the rest.
Thanks, Ted

The links below are for 81 model UK TR7 wiring diagrams that I have redrawn with a lot of information that is not in the original Triumph drawings. Hope they help you.

Cheers

Howard

Updated notes

Full 81 TR7 wiring diagram (6 sheets)

After climbing into my glove box and studying the fuse box I realized that where I THOUGHT these 2 wires connect is just the clips that hold the fuse box in place, leaving me to believe that these wires connect to the back of the fuse box. So I guess I need to get behind it and see if I can find a place for them. With the ignition on the purple wire is hot.
I'll try to get to this today or tomorrow but it's pretty hot in my garage, and I'm way too old and fat to crawl into the foot well.

I just purchased a Spider and will start troubleshooting a similar issue. This will be a tremendous help!

@ jb4249
your two sons, purple and green, connect to the turn signal unit
view the photo
friendly
Olivier

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a very good day to all

That's a great help, thanks. The flasher unit in the glove box turns out to be the hazard flasher unit. I found the turn signal flasher unit in the driver side foot well. But putting the hazard unit in provides power to the hazard switch which in turn powers the turn signals. I've managed to get that power cut through to the TS switch and still no turn signals, but I have found that the TS switch has been replaced before. The wires are connected with wire nuts that I am going to replace with soldiered connects. From there I can also test the TS switch to see if it is operating correctly.

I soldiered the connections and tested the TS switch and it does not close the contacts as it should. I am going to order a new TS switch and see if that gets me turn signals at last. i'll probably order new flasher units for TS and hazard too.

In case you do not have a fuse label on your fuse cover I have remade a couple. There are around 10 different part numbers and I will be trying to see if there is a pattern as an early one I have had several 10 amp fuses but they all seem to be 20 amp by the time of the later part numbers.

These two are from a left hand drive TR7 and also the part number quoted in the TR8 drivers handbook AKM4779 (blue one ULC3121) and a UK spec Solihull TR7 as well as one of the rare 18 right hand drive UK spec TR8s (black one ULC2323). Any images and input gratefully received!
I have copied these faithfully - down to the full stop missing on fuse 13 14 and the difference in heights for the spacers (large capital I but from a font that puts a bar on top and bottom!)

Please send any images, details of fuses, part number and VIN / car it is on (eg LHD TR7 efi 1980) - all gratefully received!

After tracing the circuit from the glove box hazard flasher unit, through the hazard switch, (cleaned that) to the driver's side foot well and the turn signal flasher unit to the TS switch. Determined that the switch was bad, so I got a replacement from TSI and still no turn signals. When I used my 12 volt test light and touched the wires putting power into the switch and out of the switch heading to the turn signal lights at the front and back of the car, that made the TS start working. So I am pretty sure my root problem is corroded grounds, or maybe just dirty. So next step is to clean all of those connections.

hi ted, here is the solution that I posted on another forum to clean all the pods
and apparently there were convinced


..( dipped in hydrochloric acid two minutes, then in soapy water to stabilize, Finally 80 ° heat gun drying and finally spray contact w40, suddenly it is like new ...)

You just remedied the most common cause for electrical failures on these cars, corrosion of contact surfaces
As long as all contact areas are kept relatively clean these cars are pretty reliable from an electrical point of view

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a very good day to all



Edited 1 time(s). Last edit at 2018-07-14 11:31 AM by oliviertr7.

Hey, just curious, what type of relay are you using on the drivers side foot well? Is it a two or a three-pronged relay? I have three wires in there, but only two are connected to a two-pronged relay. Also, which wires are you connecting if you are using a two-pronged relay? There are two greens and a purple. Any help would be greatly appreciated !!