Electrical problem with headlights

[Davbat63]

Hi, I've recently replaced my headlights with NOS Lucas halogen units, these were the same as previously fitted. I have also refurbed the dashboard & bulkhead area, with everything thing appearing to go back together correctly...
The problem I have is when I switch my headlights on, I have all 4 illuminated with main beam lit up on the warning cluster, I have connected another switch assembly and this hasn't made any difference, with the switch forward or back main beam stays on...
Has anyone come across this fault before? Have I missed something really simple as this fault has me really baffled...
Any thoughts appreciated.
Thanks Dave

[StagJonno]

Sounds like a wiring fault, though could be a faulty stalk switch. Would help to know how were the lights operating before? Standard, at least on "Mk2" is that outer headlamps come on with the rotary light switch unit, putting on main beam with the stalk puts the inner headlamps on (with an H1, single element bulb). Quite a few owners have fitted H4 headlamp units for either (or both) the inners and outers, hopefully using relays, to give any combination up to 4 lights on dip and 4 on main.

What lights come on with the rotary switch off and the main beam flash stalk operated?

Jonno

[Rolling Road]

Hi Dave
I have had something similar, on a 1977 production, but with one main beam coming on with the dipped lights! It was ultimately earthing related and you are in good company as like you I fitted a new switch first. My problem was also because relays were fitted and one was switching as a route to earth when dip was selected.
First question is then do you have relays fitted? Are the lights the same brightness? As the signalling cables go via the fuse box, check the voltages there with the fuses out to establish if the voltages are originating from the dashboard or not. Then with the fuses in and the lights powered up, check if voltages are the same at each fuse, with the lights powered. If the bulbs are new and the same wattage, if the voltages are not the same (you may need a digital voltmeter for that), then its almost certainly earthing related.

I ended up rewiring so the relays drew power direct from the battery positive (via a fuse, with relays mounted in the space behind the grille) and using the original wiring as signalling cables for the relays only. I also cleaned up the earthing side and used nickel grease on the contacts (Nickel grease conducts and keeps corrosion away). Worked a treat, so much so that all became brighter, which made me take pity on her and splash-out on Cibie globes, which are superb! Most of the electrical problems I have had with the Stag are generally related to poor earth contact or fuse supply contacts, which deteriorate over time, which is why I now coat earth connections with nickel grease after cleaning up. Had no problems since. Hope that helps you.

[sujitroy]

I think you have wired up something wrong. Disconnect all the wires and start with 1 light only. Start with main then dipped. Repeat for the second light on the same side, then move over to the other side. The wiring loom goes to the lights from the horn side of the car. (Fed. cars it does) Start that side.

I had an interesting problem when I switched the outer lights to LED, but left the inners bulbed. In the end I disconnected the inner bulbs.

[sujitroy]

As mentioned by Rolling road, one wire is being earthed.
Sujit

[Phil S]

also check the dip/main contact on the stalk switch. if you don't have the lights relay operated it could have welded it's self in the main position due to the extra current draw.
I have installed 3 relays
1. ignition powered that feeds my DRL's and the outer 2 relays
2. feeds dip
3.feeds main
this way you can only leave your sidelight on if the ignition is off