TReslaV8 Posted January 8, 2018 Report Share Posted January 8, 2018 Had a great run in the TR7 V8 this weekend but then washed the car to get rid of the muck, step back to admire the gleam, and one headlamp pod is raised..then gradually jerks down in steps until closed, when the other side jerks up in 4 or 5 steps to fully raised, then jerked down and reverts to other one, and so on. Slight electrical burning smell in cockpit, so undo fuse cover and which fuse? Couldn't find anything in manuals other than which one is dipped beam - removed those but no effect, the pods are still winking alternately. So tried turning ignition on and switching on the lamps, no joy, turn off ignition and pods still winking at me. Finally disconnected battery as the burning smell is a worry. Reconnected and they start again. Disconnected the battery again, timing to coincide with the brief moment when pods are both down, and hey presto, once reconnected they stayed down! No burning smell and working headlamps. Any ideas anyone? Surely not just water on the connections from where I washed it? I washed by hand so not a question of high pressure water jets getting to where they shouldn't. Thanks David Quote Link to post Share on other sites
Chris1966 Posted January 8, 2018 Report Share Posted January 8, 2018 Hi David, Have you tried pulling the headlamp switch out (with battery disconnected) to see what happens on reconnection. That would let you know if the problem is with the switch. Many years ago when I had my 7 the switch just suddenly failed. If this does not get you anywhere you can pull the motor connectors and manually raise the headlamps as a temporary fix. Chris Quote Link to post Share on other sites
bob-menhennett Posted January 8, 2018 Report Share Posted January 8, 2018 David " Battery disconnected " unless you want one less digit or part of a digit , seems to be the overriding advice before you attempt anything. A search on the TR7 / 8 Forum throws up these hits : - Headlights clicking problem O/S Head Lamp goes up and down OFF side front Headlight stopped rising Headlights popping on and off spontaneously An Internet search ( " Wedge Headlights- Team Net " ) throws up a good article Invasion of the Pod People ....lost of useful diagrams that can be enlarged on screen. A good check over , clean up of electrical connections , general lubrication seems to sort out a lot of the problems. Good luck with it , let sus know how you get on. Bob Quote Link to post Share on other sites
RobH Posted January 8, 2018 Report Share Posted January 8, 2018 Well I don't know whether you have a manual but this is the relevant part of the circuit David. Part no 7 is the headamp breaker (fuse?), 8 and 9 are the relays which operate the motors 13 and 14 respectively. 11 is the headlamp flash relay and 12 is the main light switch: There's a post describing the operation that you might find useful here: https://club.triumph.org.uk/cgi-bin/forum10/Blah.pl?m-1352379828/ Its difficult to see what in that could cause the lights to cycle alternately nor to make them operate in jerks - though I suspect the latter shows the motors were not getting full current and the jerking was due to mechanical stiction, so that does suggest it may have been a short due to water ingress somewhere. Quote Link to post Share on other sites
HowardB Posted January 8, 2018 Report Share Posted January 8, 2018 (edited) David I prepared a set of drawings with detailed notes for my TR7 explaining exactly how the lights work which can be downloaded from this link as the existing Triumph drawings were impossible to follow so hope these help you:- https://drive.google.com/open?id=0B0OCjgNgn85aOEdlYWp6dnFfc2s For what its worth I would check the earth connections first as these can cause lots of strange effects. Cheers Howard Edited January 8, 2018 by HowardB Quote Link to post Share on other sites
TR8IAN Posted January 8, 2018 Report Share Posted January 8, 2018 Hi David After a week of getting strange warnings come up on my modern car I think there are things that you can do to your TR to help your issues. Follow the advice of the others above: Firstly disconnect your battery. Undo clean and remount all the earth points - there are two under the bonnet for the headlights (Black wires bolted down to the body by the headlights) Undo the two red plugs and clean the terminals - try putting them back together with a smear of Vaseline or dielectric grease Remove the light switch from the dashboard - strip it down and clean the terminals (not very difficult - but take photos as you go so you know what you are doing putting it back together again) Also take care to get the dashboard and wiring back in properly and do not over tighten the screws as 30 odd year old plastic soon breaks. Worth also undoing the earth points within the boot (not connected with the headlights but will make all the lights show better. Hope this helps - shout if you get stuck with anything. Cheers Ian Quote Link to post Share on other sites
unclepete Posted January 12, 2018 Report Share Posted January 12, 2018 I had a similar problem and went through all as Ian above has mentioned. I eventually found that one of the diodes had failed (popped) in the lamp control box. There are two in each lamp raising/lowering mechanism, I think replacements cost me 80p each, a bit of deft soldering and hey presto all worked fine! I should mention the fun I had taking each of the headlamp assemblies apart at least twice! Good luck Quote Link to post Share on other sites
Darth V8R Posted February 23, 2018 Report Share Posted February 23, 2018 I had a similar problem and went through all as Ian above has mentioned. I eventually found that one of the diodes had failed (popped) in the lamp control box. There are two in each lamp raising/lowering mechanism, I think replacements cost me 80p each, a bit of deft soldering and hey presto all worked fine! I should mention the fun I had taking each of the headlamp assemblies apart at least twice! Good luck Pete: I concur. If one has a shorted diode, power flows back through the headlight motor run/stop switches to the both headlights. They will both cycle up and down until both headlights are fully closed at the same time and both stop switches open simultaneously. Since there will inevitably be a slight difference in motor speeds between the two headlights, the will both continue to cycle up and down indefinitely, unless you are very lucky. You need to track down the bad diode and replace it. They can fail in an intermittent sort of way before failing completely. If a diode fails open, one headlight will stick in either the up or down position, depending on which diode fails (there are two diodes per headlight). If a diode fails by shorting, you get the winking headlight problem. The good news is that you can test all the diodes without uninstalling the headlights. You unplug the wiring harnesses inside the engine compartment, and use your ohm meter on the wires going to the headlight motor. If you look at the schematic in the ROM, you will see that you can test all four diodes in both directions (forward and reverse) and determine which diode on which headlight has failed. Then, as you stated, you remove the headlight and replace the bad diode. Problem sorted. Vance Quote Link to post Share on other sites
TSD Guy Posted March 4, 2019 Report Share Posted March 4, 2019 I understand how to test the diodes and to replace them if they are bad. Can someone help me with the specifications for the replacement diodes? Thanks Quote Link to post Share on other sites
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.