johny Posted February 8 Report Share Posted February 8 That either means theres a massive current draw and you would have a blown fuse or lots of smoke! Or theres high resistance upstream somewhere like at a fuse or connector.... Link to comment Share on other sites More sharing options...
johny Posted February 8 Report Share Posted February 8 Do the same test while progressively working back up the supply until the volts dont drop and thats where your high resistance is👍 Link to comment Share on other sites More sharing options...
Jonah Posted February 8 Author Report Share Posted February 8 Thanks Johny, that’s going to need a few coats of thinking about! the next point up the supply should only be the fuse connection itself , unless there’s some wiring mod done over the years Link to comment Share on other sites More sharing options...
johny Posted February 8 Report Share Posted February 8 So not the purple to brown connector? It could be the fuse assembly itself even though the same fuse probably supplies other things... Link to comment Share on other sites More sharing options...
DanMi Posted February 8 Report Share Posted February 8 54 minutes ago, johny said: I think the lights all working ok Dan except flash so brown/red to blue/white good and failure is purple to brown to blue/white.... You are correct, photo is a little confusing as to which wire goes where when they cross. If the voltage drops to zero when flash is pulled I would check for loose/dirty connections in the purple feed 1 Link to comment Share on other sites More sharing options...
DanMi Posted February 8 Report Share Posted February 8 6 minutes ago, johny said: So not the purple to brown connector? It could be the fuse assembly itself even though the same fuse probably supplies other things... The same fuse supplies the horns so if they work the fuse connection is OK Link to comment Share on other sites More sharing options...
johny Posted February 8 Report Share Posted February 8 Might be separate wires going onto the fuse holder so there could be crusty connector for the flash supply? Link to comment Share on other sites More sharing options...
Jonah Posted February 8 Author Report Share Posted February 8 progress Took the fuse out, put it back and now the flash works…….but no horn! theres 12v at the relay on the purple wire from the fuse, now to check the steering column connections Link to comment Share on other sites More sharing options...
DanMi Posted February 8 Report Share Posted February 8 for the horn check the earth strap across the steering column UJ and the strap from the grease point on the rack to the column, these are often missing Link to comment Share on other sites More sharing options...
Jonah Posted February 8 Author Report Share Posted February 8 Just changed the steering rack! Link to comment Share on other sites More sharing options...
Jonah Posted February 8 Author Report Share Posted February 8 The car has one of the new style couplings at the end of the column Link to comment Share on other sites More sharing options...
johny Posted February 8 Report Share Posted February 8 First make sure the fuse is a real good contact as the horns also draw quite a current and wont work without a good voltage. You can try the volt drop test again at the relay supply purple wire when pushing the horn button... Link to comment Share on other sites More sharing options...
Jonah Posted February 8 Author Report Share Posted February 8 The connections at the back of the fuse box where the wires connectseem suspect mum also going to check the earth through the steering column to the rack, seems to much of a coincidence when I’ve just changed the rack Link to comment Share on other sites More sharing options...
Jonah Posted February 8 Author Report Share Posted February 8 Not my mum it’ll be me!! Link to comment Share on other sites More sharing options...
Colin Lindsay Posted February 9 Report Share Posted February 9 19 hours ago, johny said: This is getting difficult as 'swopping brown leads'? Theres only one brown coming from the column switch That's me thinking out loud again; I was studying the photo but it was confusing with the brown / red and the brown looking so similar - I can't see the red strip on one. As long as you can see yourself that it's connected properly then that's not the problem. Might be the switch, then. Link to comment Share on other sites More sharing options...
johny Posted February 9 Report Share Posted February 9 Its alright Colin problem solved and we're onto the horns now - keep up😂 Link to comment Share on other sites More sharing options...
Jonah Posted February 9 Author Report Share Posted February 9 Lights working fine now but horn not there’s no earth connection at the steering wheel via the rack, I put a temporary earth link to the coupling with the rack and we have a horn! I’ve just changed the steering rack and the car has a new style coupling without the earth strap, the horn worked with the previous rack and I can’t see where this different Link to comment Share on other sites More sharing options...
DanMi Posted February 9 Report Share Posted February 9 Is there an earth strap from the grease point on the rack to ground. You may need to make up a lead to go between the 2 pinc bolts on the UJ Link to comment Share on other sites More sharing options...
Jonah Posted February 9 Author Report Share Posted February 9 No there isn’t one there, I connected a lead between another earth point and a pinch bolt and it worked would the grease point be earthed through the rack U bolts? Link to comment Share on other sites More sharing options...
Pete Lewis Posted February 9 Report Share Posted February 9 the normal rack sits on rubber mounts and any chance the u bolts earth with all the grott that collects is unlikely some earth the rack to the front engine plate i have seen a sprung contact thats bolted to the bulkhead and rubs on a cleaned bit of the steering shaft to bypass all the uj and rack earth problems Pete Link to comment Share on other sites More sharing options...
DanMi Posted February 9 Report Share Posted February 9 I think that mine is going to one of the mount bolts for the radiator frame but any body earth point will work. It wouldn't earth through the U bolts without a lead as the rack is insulated by the rubber bushes (unless you have solid rack mounts) Link to comment Share on other sites More sharing options...
johny Posted February 9 Report Share Posted February 9 Jonah have you downloaded the workshop manual for the Herald and Spitfire at vitessesteve.co.uk as it has lots of this useful info? Link to comment Share on other sites More sharing options...
Gary Flinn Posted February 9 Report Share Posted February 9 (edited) I think the original earth connection was from the Grease nipple/bolt item 35 on this still to the underside of the Steering Rack 'U' Clamp Item 53/55 nuts. Like Pete says, you need to make sure there is a clean connection to the chassis with the Clamp/Nut, or alternatively use a one of the bolts on the Engine Gary Edited February 9 by Gary Flinn Link to comment Share on other sites More sharing options...
Jonah Posted February 9 Author Report Share Posted February 9 The chassis has been coated with epoxy so probably provides an awful earth connection I’ll try a strap from the grease nipple/bolt to another good earth point ill download the manual also and will report back 1 Link to comment Share on other sites More sharing options...
Jonah Posted February 13 Author Report Share Posted February 13 Thank you everyone for your encyclopaedic knowledge and insightful comments, thanks to you I now have working lights and horn one connection into the fuse holder was loose against a fuse which now tightened has given me light after changing the steering rack putting an earth strap between the drain plug and an engine mounting bolt has produced a welcome sound from the horn thank you once again 1 Link to comment Share on other sites More sharing options...
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