Headlamp issues (resolved temporarily)

[dapinky]

As many (most?) of you know, I am quite happy with big oily parts of the car needing spanners and hammers - but not quite so comfortable with the electronics....

.... so I am after a bit of advice from those who either have a clue, or are better at reading circuit diagrams than I am (which is most people!!!!).

The back story - my green Elan went into the garage 3 years ago, and was regularly started and driven short distances until Angie needed a battery to get her Corsa home from work - and it never got replaced. So, for 2 years it has just been sitting there, gathering dust.

Anyway, I decided to do something about it, and bought a new battery, which (despite being advertised as "In stock for next day delivery") was delivered today (ordered last Wednesday morning).

So, I chucked it in after cleaning up the terminal connectors, and had 2 immediate issues - the alarm fob didn't do anything, despite the blue LED flashing on the dash, so the immobiliser won't disengage - it is a Clifford system, of early 90's vintage, so I have no issue with ripping it out and fitting a new central locking control fob box (like in Angies car) - so, that will be tomorrows job to trace the wires and sort them out. (maybe getting it to work, maybe removing it - time will tell). The door locks activate with the lock buttons, so it is the Clifford system at fault - I've tried both fobs, with the same result, so it is probably the box in the car...... as such, i couldn't try the rest of the ignition system, so decided to check the bits I could - which is where this post comes from.

The side/tail lamps are fine, so i tried the headlamps - both illuminated, but only the pax side raised....... until I gave the linkage a bit of a wobble, and then both light raised and worked.

All good, until I turned them off, and they both went down - except the pax side then half-raised, didn't illuminate and it went up when i twiddled the knob on the motor. When turning it off, it dropped, then half-raised again - and I noticed that the motor was warm to the touch.

I appears to have current permanently to the motor, but I ran out of time, so disconnected the battery for this evening.

Looking at the hieroglyphics which some people seem to fully understand, but I have a very rough understanding of, it appears to me that the switch is okay, as is the pod delay module (otherwise it would affect both sides????) - so I am drawn to the big thingy on the bulkhead (pod lift module). From my reading, the left and right sides are separate, and should provide 12V when the switch passes current to the relay, on on to the module.

I have yet to dig out the multimeter due to time, but am I in the right area????

Should there be 12v out of pins A & C (earthing via B&D), specifically pin C for the LH motor????

Is this a known failure (I know Joao has had issues in the past and replaced transistors)?

Is it a good idea to swap it for the one on the other car at an early stage???

[peteoddcar]

Dave
I’d like to help if I can. I’m assuming it’s been dry stored?
Before reconnecting the battery.
Alarm - I’d first fit a new battery to one of the fobs probably the one that you used most.
It’s odd that just being disconnected for some years would cause the Clifford to fail. It may be the fob needs pairing?

Headlamps
I’d disconnect the rods on both lamps, wind the motors back to the closed position, reconnect the battery and watch what happens to the motors when you do a headlamp flash.

[dapinky]

Pete,

Thanks for taking the time to reply.... fortunately you understand the electrics in these cars (which i don't!).

'Dry' stored is a disputable issue, as the garage does suffer from damp issues, being underground and the water table is variable here, leading to seepage of water at odd times (usually summer).... but, yes, basically dry, but with a bit of humidity.

As such, your advice to remove the rod linkage ties up with Joaos thoughts (by PM as he couldn't post here yesterday) that there may be too much resistance in the joints, and the electrics think it's fully extended when it's not.

The new battery idea is something which I never thought of (because, why look at the basics before starting on the extremes?) - I did try both fobs, but no results. Maybe they have lost their pairing , maybe they have flat batteries - I'll try that today.

Note to self - don't just assume the worst - think a bit more logically!

[RonR]

AFAIK the headlamp raise/lower module works by sensing the current drawn by the motors, so stiff joints could cause the module to think the motors are at the end of their travel when they're not. Mine did much the same last year.

If you need them the headlamp pod ball joints were available last year from B&C for a few quid, a couple of mine had disintegrated - just drill out old rivets & rivet in new ones, remembering to slather with copper grease!

[dapinky]

A mixed day of fortunes today - but heading in the right direction.

The alarm issue is sorted - 2 new fob batteries, and digging out the paperwork for pairing the fobs to the system got it all going...... I just needed to find the PIN code for the system, which was in the paperwork from when I first bought the car.

But before that, I located the magic box, pulled out the immobiliser plug/socket and shorted the connections to get rid of the circuits, which gave me ignition lights on the dash. Gave the unit a good old-fashioned slap with my hand to stop the annoying chirps from the siren, and flicked the key to turn it over. It took a bit of time, then fired up at a rough idle, before dying again.....

Yes, you guessed it, I needed to reset the switch in the hood stowage area. I don't know if I disturbed it when doing the battery, or if (more likely) I had flipped it when putting the car into storage - I simply can't remember. Still, it then fired up and settled to a nice(ish) idle. Not bad for 2 years standing, and at least I circulated some oil before it fired up properly. It will get new petrol next week anyway. I drove it forwards and backwards by a few feet (couldn't be bothered to move the blue on out of the way) to check the clutch was free, and the brakes were not jammed solid. It has been left without the handbrake on, so it was only binding a bit, and freed off pretty instantly - obviously I will sort them properly before venturing out of the garage.

Back to the Clifford, I re-did the connections and fiddled with the PIN codes, and ended up with 2 working fobs.

The headlamps still playing up, and it appears to have 12V permanently applied to the motor, which is getting very hot. This is irrespective of whether the light switch is on or off, and with the ignition connected or otherwise, so probably not connected to the earlier alarm system issues.

Temporarily 'sorted' by simply unplugging the motor (which still showed 12V at the plug)..... and then slightly more permanently by removing the 15A fuse from C1 under the dash binnacle.

Now the lights all work, but the NS needs winding up by hand, whilst the OS works as intended.

So, my understanding of the wiring diagram suggests that the lift module operates as 2 separate 'switches', with a wire to both illuminate the dipped beam, and operate the motor.... but the lamp lights as intended, so that bit of the module appears to be okay...... so am I right in thinking that something inside the module is knackered??? (MOSFET rings a bell from what I have seen written by Joao elsewhere) - or maybe just something sticking??

Should I take it out and open it up - if so, what am I looking for (burnt parts?, stuck switch?, dirty contacts? something else entirely?) - I can swap it for the one in the blue car for now - but I have to admit, I am happy to have a go, and learn along the way (with guidance!)......

.... or should I bring the duff one to Castle Combe to see if anything is obvious to someone else ( ) - assuming the other one works!

For now, I am moving on to things I know about, and don't faze me at all - I will remove all the brakes and sort them out over the next few days, and put it in for an MOT (the pods not raising are not an issue as the car will be tested "as presented" with both pods raised manually).

Then it'll be an oil change and new petrol, and see how it behaves.

All lights and wipers are working (haven't tried the washers yet, but they are straightforward if they don't work) - the number plate lights needed a wiggle to the LED wiring strip, but that was noticed at the last MOT anyway, so no surprise.

The windows both work, but are very sluggish - I have all the parts to rebuild them (sliders/butterfies etc), but as we all know, it isn't a 5-minute job, so is well down the list at this stage.

I may even change the cambelt, just for the hell of it - but not top priority.... if I have half a day spare before CC, I may do it.

Oh, the bodywork is looking quite poor now - the respray 10 years ago hasn't lasted well, and it is covered with microblisters, and what looks like mould spots under the lacquer - still, I can't see it from the drivers seat, so I am not over bothered.

[Tuga2112]

the respray is quite a shame. your car did look very good back when i last saw it.

as far as the unit. i have a few pictures in the desktop (currenly on the work laptop) that i can send you as a reference to what your expecting to see.

burned stuff is what your looking for, there are no capacitors to bulge in the circuitry but with the refenece pictures, you will have some idea of what "working with a broken mosfet" looks like

i can have a dig for the spare mosfets (as mentionedin the PM) the synmptoms are different to what i had, but it may be the same issue.

[dapinky]

Thanks Joao - first thing is to swap it over and see if that cures the issue - if so, I will open up the unit. (but the brakes will take priority for now, as I can cope with the lights not lifting on a switch)

[peteoddcar]

Dave
Great progress - could I suggest you try the suspect module on the good (blue?) car? If the failure transfers to it then ok you have it sussed but I would only try the good module when you are sure the other one is bad also leave the “getting hot” motor disconnected at first then connect it to get hopefully a fully working green car albeit needing a module repair
Jaoao I’d like you to share the photos you have
Thanks

[dapinky]

Pete, that makes sense.

From lots of reading, and a post made by geoff a while ago, referencing a Corvette C4 module repair, I am drawn towards a duff relay inside the module (but I have no reason to go on, other than the symptoms on the guys' Corvette seem to match mine, and his description of the problems sound logical...... https://www.instructables.com/C4-Corvet ... er-Repair/

..... and I can get a new relay for under a tenner, so hopefully, it won't be a dear fix (but who knows!)

[Tuga2112]

..... and I can get a new relay for under a tenner, so hopefully, it won't be a dear fix (but who knows!)

its not a "standard relay"

last night i spent 4 hours drilling and trying to tap one of the bolts in the turbo housing.. when i got back in the house i completely forgot about the pictures. hopefully ill remmeber when i get back home after work today.

[dapinky]

..... and I can get a new relay for under a tenner, so hopefully, it won't be a dear fix (but who knows!)

its not a "standard relay"

Nope, it's an Omicron 14-pin 4 pole unit......

There are cheaper versions for about 6 quid, but this is a known make.

I then need to decide if it should be soldered direct to PCB, or should I fit a socket (is there enough clearance inside the case for the added height?).....

..... anyway, that is down the line, as I have been having other thoughts about it all - I know the unit is supplying 12v permanently, but is that because it hasn't detected a 'stall current' from the motor (which is disconnected) - in which case, could the fault be in the motor or the 'logic' circuit inside the module???

I will go with Petes advice of fitting the "suspect" module in the blue car and see if the problem transfers, or if the module is good - that will help direct the future investigations to either Module, Motor or Elsewhere....

I'm just glad that today is a 'brakes' day!

[dapinky]

Okay, so from the change in thread title, it should be noted that the headlamps on my elan are now working completely as they should.......

...... but the ones in the blue car don't!!!!

Okay, so I put the job on the back burner whilst I sorted out the brakes - after 3 years of inattention, 3 of them were still free and sliding (but still got stripped and re-greased, with new slider rubbers where 2 had split)..... only one was a bit of a PITA. Surprisingly, it wasn't even a rear one - but the FNS calliper had stuck sliders (freed off with a bit of effort, and reassembled)... then I noticed that the piston appeared to not move (ie, the pads wouldn't slide into contact with the disc when it had all been de-rusted and reassembled).

Application of a prybar failed to shift the piston, so off to the loft we went to dig out a calliper seal kit. I couldn't find one, so decided that I'd just stick a new calliper on for now to get it good for the MOT - sounds like a sensible option, but failed to allow for the clumsy pillock who was collecting the new calliper from the box in the loft.

Did you know, that a chunk of cast iron weighing about a kilo and a half (even when encased in a flimsy cardboard box), dropped from the height of about 8 feet onto a ceramic WC below the loft hatch could cause a "slight" problem??

Anyway, I had quite fancied a new bog in the separate bathroom for a while, so the large crack which caused water to flood through the ceiling into the hallway below simply allowed me to move that job up the list a bit. (somehow the calliper missed the cistern and hit the side of the pan hard enough to crack it through the 'U' bend).

So, work on the brakes also came to a bit of a stop, whilst I whipped out the old bog, lifted the flooring and set up the dehumidifier to dry out the floor (and ceiling below). Then I fitted the new calliper, bled the system, had a good pedal, so went back inside.

As the floor is nearly dried out, and I felt confident enough to try the lights in the hallway (all okay!), a new close-coupled system is sitting on the landing, and the old stuff went to the tip this morning, and needs to be fitted tomorrow, I thought I'd go back to the car......

..... in the meantime, the new seal kit has arrived, so I rebuilt the old calliper and (very carefully!) stuck it in the box in the loft, so I still have a good pair ready-to-fit.

So, I thought I'd check some other MOT bits out (putting off the headlights!!!!!) - wipers fine, washers not-so-much.... bit the pup was working and a bit of fiddling ascertained that the one-way valve was bunged up..... emptied the reservoir, dismantled the pipework, got it all working without the valve fitted. Blew out the valve with compressed air, re-fitted, all good.

As a surprise to everyone (especially me) the hazard lights (including switch illumination) work fine. The horn sounds a bit asthmatic, but at least it sounds, so that is also ticked off.

Oh, I forgot, this is meant to be about the headlamps.......

.... I removed the pod lift module and before I even thought about whether to try the good one in this car, or this one in the good car, I was hit by the smell of burnt plastic - so i opened up the box and was presented with the following scene.

Now, I may not be much of an electrical engineer, BUT I am a reasonable detective - and by using all my senses, and applied logic, I realise that the MOSFET is f$%*ed - or certainly a little past it's best.

Now, how much else is also possibly damaged is beyond my ability to discern - but if only there was a chance that I may bump into someone this week who has the knowledge, tools, and time to take a look at it for me..... maybe even fit a new transistor..... oh, and if they had an Elan of their own to test it all on - happy days..... maybe a retired rocket scientist......

...... if this rings any bells (Smiffy, I mean you! ) feel free to offer your services

So, there we have it - the module from the blue car is now fitted to the green one, and everything works - so, as per title of the thread, issue is resolved - or more correctly, identified and transferred to the other car.

rear of PCB.jpg

front of PCB.jpg

transistor.jpg

[Tuga2112]

when i saw that this post had the update i thought "well this time im actulaly in the desktop, ill get that picture" but seems like theres no need for it.

found the mosfets. (within seconds... for a change something in my house happens to be organised)

however, im not either presently or formely a rocket scientist

[peteoddcar]

Dave
I’m sure that you’ll get it sorted by someone at Castle Combe if not by any chance seek out Chris M and he can hand it over to at our next meet up.

[dapinky]

Pete,

Thank you for the offer

I currently have a selection of plans available to me - firstly, the car is working, so it just means that Angie can't take hers out in the rain (no chance of that) or at night - equal chance to the first option!

As such, I need to get it sorted, but it is now far less of an urgency than it looked like last week. Jonathan has kindly offered me a loan of his spare unit, so that will get both cars back to fully operational. A bag of MOSFETS is due to be delivered tomorrow, so I can stand at Castle Combe with a burnt plastic box, a bag of (hopefully suitable) parts and a look of forlorn hope on my face..... and if that doesn't work, then I may well ask Chris to pass it on to you.

[peteoddcar]

Dave
Keep us posted on the progress.

[GeoffSmith]

Not good Pete. Board was charred to buggery and replacing just the burned out MOSFET and 6k8 resistor didn't help.