Talk Morgan Forums Morgan Sports Cars Morgan Three Wheeler & Super 3 Dip lights suddenly out ? Help

All of a sudden my low beam dip everyday headlights are out ? I check fuses of course ,I switched out all four relays , I installed a brand new turn signal module .
In trouble shooting , I noticed the “ dip beam “ 15 amp fuse is “ never hot “.
My headlights only come on if ignition key is on ( normally that is - and if headlight dash switch is flipped on ).
Either way no voltage to the dip fuse ?
Key on , light sw on . Strangely enough my high beam /main works with pulling stalk back . And that fuse gets voltage when I do.
Also my “ dip lights in idiot dash light illuminates when light switch thrown and my high/ main beam dash idiot light illuminates when I flash main / high beam. Does or did anyone have a similar problem ? Can anybody tell me where main feed to fuse block dip beam … would come from ? Ignition?
The idiot light is getting power ? What’s supposed to be switching power “ on “ to that dip beam fuse . Thanks

The headlamp flash is on a dedicated circuit with its own relay so not surprising it works when dip doesn't.

Suspect the dreaded TSM module which interprets stalk actions for indicators and headlamps. This unit then provides the switching signal to the dip/main relay on orange/blue cable. The dip output from relay then runs to fuse 17 via blue/pink cable and on from fuse to each headlamp on pair of blue/red cables. If main beam is working normally it's safe to assume the main power to dip relay (two blue cables) is OK.

The dip/main relay is wired for dip failsafe. Strangely this suggests the TSM module is providing a permanent main beam switch signal. You could prove this by interrupting the orange/blue feed to relay (if possible) at which point dip should come on.

Man o man ! You know your wiring . Nice 👍🏼. I know my stuff too. But I’m struggling . Many many hours in this over months . I really appreciate your help. Maybe you like a challenge. Can you tell me the following, cause it’s been killing me .
A) if facing front /car motor - what’s relay ID layout ?
I surmise , left rear -main beam , right rear -fuel pump
Front two ?
B) should my dip beam lights come on without key turned in ignition ? Or only with key turned to start / running ?
C) I’m running round led halos in normal h4 lights . I’m tapping off a lead that was in my headlight bucket 🪣. It’s switched from exiting dash light sw. What the heck is that lead ? It’s working fine.
My push forward lock on main stalk function has never worked. I replaced TSM. Stalk tested / switched all 4 realty’s and flasher relay . Arrrugh tons of hours ! Lol
Yesterday I lost my dip normal everyday light ? Being technically capable . I checked the dip fuse 15 amp . And I believe , I’m correct but , there’s no voltage ever ( key on / lights sw on . To that blue 15 amp fuse ? Like the feed side of that fuse is not getting juiced . Right next to it the blue main fuse does guy juiced when key turned - then if I pull stalk main comes on 👍🏼 That’s what dip fuse should work like . Dip fuse supply side dosent appear to get loaded /12v ? I’m suspecting my dip relay ? Vaguely, cause I’ve switched my relays with new ones a boat load of times . However I do not hear a click of relay when I throw headlight dash sw. ? I do hear the main relay click when I pull stalk 👍🏼
Thanks for color codes priceless, I know several . But vey help full.
Thanks I will keep at it
Ps I’m tapping off switched hot if dash light with 15 amp fuse and going badass direct to my h4 dip beam element ?
Any thoughts ? 😆

May help more info - I’m noticing my dip fuse, Fog fuse, side/instrument, and side fuse. Do not have power with key on or off ! Lol the main beam fuse seat,fan,intercom.ignition fuses do have power . I mention this cause it may help you “ read” issue . Are those items that are “ out” all controlled by dip relay ?
I’m told TSM does not drive any headlight functions?
So I’m getting relay suspicions?
Thanks

Mogegg, the TSM (turn signal and headlamp module) does control headlamp functions as mentioned.

The fusing is sometimes after the switch that selects the function the fuse protects. As already explained the dip headlamp fuse will not be live until power is received from relay, and this won't happen whilst relay coil is energised leaving headlamp main beam selected. To prove this with ignition and headlamp main beam on you will find fuse 16 live but fuse 17 dead.

Don't have my M3W anymore to check but dip/main relay is the one with all five pins connected and orange/blue control cable.

I think the redundant cable(s) in headlamp shell may be for position lights which are not used in US models I believe.

It appears you don't have M3W parts book which contains engine and chassis wiring schematics. Suggest downloading here.

Mogegg, just read your most recent past here which gives me a better understanding of your issue. Apologies if I didn't fully grasp the problem earlier. From your most recent description the multi-function stalk and TSM, which you have replaced anyway, seem to be operating correctly in as much as indications on instruments conform to stalk commands. Hopefully you have downloaded the parts book I linked to above which contains the wiring loom schematics. These can be difficult read but it's where I gain my info.

The headlamp main beam flash is essentially independant of the headlamp switch, has its own relay and independant power from fuse 7. As it works correctly no reason to dwell on this.

The issue now seems to point to main feed to dip/main beam relay which comprise of two blue cables, U96 to TSM and U129 from instrument connector plug. The latter is probably the feed from headlight switch, looping back to TSM at relay connector. Without power to this relay whether dip or main is selected, no power can pass through it to either headlamp beam.

Best advice I can give at present is to check the 12 way instrument connector behind dash, C31 on schematic which includes connections to headlamp switch, and whilst there check connections to that as well. Until you have power on U129 (blue cable) there is no way either headlamp will work when selected, so may be worth tracing this cable from dash connector to relay for any breaks.

Don't worry about power to fuses, they are in circuit after the fault, and as main beam works on flash no reason to assume the dip fuse is faulty either. Finally although I haven't seen mention of model year, above advise applies to early or late models.

Please advise on outcome.

Thanks so much . You guys are really capable and insightful. I am highly technical self taught, but my talents only go so far. I do have wire color code pages and they are like secret code breakers 👍🏼 Very helpful 👍🏼 I am going to digest you great suggestions, and trouble shoot in next few days . Then I will have more insights . I had reached point that I concluded I had to trace back the power feed that should be activating the dip beams. I’m assuming it goes from ignition switch , to relay (dip), then to light filament. I’m pretty sure my car has a main beam relay And a Dip beam relay. That’s why I focused on relay purpose and suspecting (dip ) one. I have a pinpoint test light- so I can pierce a wire and test for voltage , with no damage to wire. I only said TSM does not do any headlight functions cause allister (TSM guru) wrote that. However later in his thread he says TSM DOES provide headlight functions. He explains what . I believe it’s “stalk” signals for flashing (pull) main and locking main on (push). I have tried two TSM units . And my stalk push lock on function still does not work. I also put a brand new stalk in vehicle 🚗 arruggh ! Lol. I’m going to leave my lock on main beam problem aside . I hacked right by that issue with. Wolo wireless switch 50$ so so cool ! Momentary or on , it powers two 100 w pencil beam mini landing lights. Switch pod is a small round thing - stick anywhere - dash, steering wheel, side of cockpit . Mines on a Black thermo mold outrigger, so it’s right near my steering wheel / I can hit it without taking my hand off the wheel . 👍🏼 It’s awesome/trick .It’s a shame I have to hack around my dip beam operation /headlights .
Thanks again for help. It’s so important to me . I put boatloads of hours into this stuff. It can be very frustrating and defeating . Your tech advice is at a high level . I’d never give people casual /aloof advice . Your advice is great . I’m Actually working on my car / these issues tons . Advice that applies to actually troubleshooting and fixing the issue is what I need . You guys are on the ball. Thanks I will poke around and look more at stuff and then advise. 👍🏼

I see you have gone for the scatter gun approach and spread your issue under different headings just to confuse the likes of me.. (-:

Being an old geezer I kinda gave up on messing around cars in frustration when the digital era arrived and black boxes took control along with the need to swap out expensive parts to fault find..

Assuming anything in modern circuitry seems to risk a degree of confusion, so perhaps best not to..?

i.e Lighting circuits may not be fed via the ign switch..?

Back to basics thinking....? You have checked the lamp filaments of course, assuming they are not LEDs, and if LED there seem likely to be driver modules involved...?

In times past the main, dip and flash stalk is generally designed as an either/or switch with a further function to flash the main beam... also the horn would be activated by pressing the end of the stalk towards it`s base. EITHER dip OR main beam seems kinda obvious electromechanical action as does the action of the switch to flash the headlamps..?

I suspect you have proved that the switch moves freely to all those positions and holds to the either and or positions to enable selection of main and dip..

It seems probable that there may be a local plug to enable simple replacement of a faulty main/dip switch...?

If there is such a plug, it seems that the feed/live/hot, should be supplying as it should if you have any headlight circuits operating... But check it is there to be sure.

The fault could be in the plug it`s self check for signs of heat in the wires and the plug (if there is one such)

Having confirmed there is no signs of melting and or burning at the plug and that the there is a voltage available at it....

That being the case with the plug disconnected then you can hopefully use your multimeter on ohms scale or buzzer to determine that all the above switching actions are taking place within the switch, making use of the wire colours to identify and determine primarily the feed/live/hot into the switch, then operating the switch to determine that the mechanical action is creating the appropriate electrical connection, again identified by using the wiring colours to confirm all is well for each and every individual action...?

OK so with luck you have proved there is electricity available to the switch and that the appropriate switching action is taking place within the switch..?

That being the case then it is possible that when plugged up and passing POWER through the switch which exceeds that of the multimeter buzzer etc... The switch can fail under LOAD due to burned or damaged contacts.

The above scenario was oft times created when folk fitted higher powered headlight bulbs drawing more power than the switch was designed to handle and thus in time the switch contacts would slowly overheat and burn creating electrical resistance across the internal contacts where carbon would build up reducing the contact area..

I suspect if you have got this far then your pin method used through the insulation may prove that the switching action it indeed functioning correctly by switching the power through the plug and on into the rest of the wiring loom..?

With that proven where to now..? There may indeed be relays involved or not..? OK so you have a jumble of wires and a multi-plug base to confuse matters, however with luck you should be able to pick up whether or not the OUTPUT wires that you have proven should be switching as required, are to be found entering the multi-plug base...?

If not then chances are as in times past there is no relay in the circuit.

I guess another possibility may be... Now that you have hopefully proved the switching action, with the headlight switch selected on and switching between main and dip, you might hear a relay clicking to assist in proving if one such is in circuit..? Or id your hearing may not be up to the task, then if you place your finger on each of the relays in turn as you switch from dip to main or vice versa..?

Of course if no relay action heard or felt, the connections to/from the coil of the relay, or the coil it`s self could be open circuit.... Thus proving just how important it can be to make good use of the wiring colours to identify circuitry at the base of the relay and elsewhere..?

Yeah all a tad basic I suppose but then hopefully my old way of thinking might help and not just add confusion.... I`m oft times confused myself thee days..

BEWARE...I have not read over this so there may be flaws to be found..

George, to save further confusion, on the M3W there is another layer of electronics known as the TSM that interprets the movements of the multi-function stalk, unlike the four wheel Classics that employ, currently Land Rover derived, plain stalk switches which I guess we are both more familiar with.

The OP has confirmed that the headlamp flash on his M3W stalk operates main beam correctly via dedicated relay. However when selected by headlamp switch neither dip nor main work. A second relay performs this function, and since it would fail to one or the other and neither work, the suspicion falls on the power feed to this relay hence my advice as above.

Richard many thanks, I hoped that you might take the time to jump in and apply your greatly advanced know how to avoid my rambling adding to the confusion.. TSM..? Guessing Thyristor or some sort of digital device.... Time for me to bale out again...