Ianos

the flash to pass isn't working in any case so either both high beams are gone or the column switch isnt getting power and/or the column switch is broken. I'm searching for correct replacement units for the headlights and will order a pair - plan: 1) replace both headlight units 2) clean out the column dimmer contacts and switch 3) pull out the headlight dash switch and clean/test position 2 - likely try to replace with a new unit. any further ideas or input greatly appreciated.

excellent point 😅 i'm clearly not an auto electrician

Thanks v much - this is super useful information - I believe I tested the two contact points on the dimmer switch and neither were getting power.. however the fuse is 100% working, it has continuity though it - that said, just thinking about it more - maybe its the fuse box its self - many the contact points of the fuse box are not contacting correctly - but again you point out, the low beams are working and if they share that fuse than that cancels that. I am putting my money on the headlight dash no. 2 position not working - unless I can prove there is power getting to the dimmer switch, it seems to be the only possibility remaining. The difficulty is getting that switch out - its really awkwardly placed in up behind the fuse box, plus the knob seems to not want to budge off its switch column! thank again - will keep you posted

hi KR thank you for replying and helping! Thats interesting to read - I knew the column stalk switch was part of the circuit but didn't realize that it is referred to as the 'dimmer' switch. confusingly there an actual dimmer switch for the dash lights so I assumed the headlights were on that circuit somehow. As to the column stalk aka dimmer switch - i tested it out and it doesn't seem there is power getting to it. . I will have another look today if I get time but I think I tested voltage across the two contact points hidden beneath the clam shell casing, and got nothing across either positions (neutral/main beams or High beams). Currently my thinking is the pull out switch with 1 and 2 positions is the issue - and will do further investigation. any other thoughts, do let me know - , I was using that column stalk (dimmer) 'flash to pass' function before and it was working fine - but currently zip. i'll clean it out and see if that helps but without voltage to the contact points Im not holding my breath! thank you! Ian

quite update; I was incorrect earlier - only one of the two headlight units has a good circuit - the other is dead. will order two replacements. Either way, I dont believe one bulb/unit being blown would take out the second or effect the power to it - do correct me if Im wrong

Hi all Finally got around to investigating the no headlight issue - FYI its a '79 620, and the internet tells me that is a 'non relay' truck.. The back story is that everything was working fine until recently - then one side was intermittently going, followed shortly be the other. I remember at the time having been driving at night on dark unlit roads, so was using the column stalk switch to go between highs and main beams, I had figured that that bit of use might have been the issue - wearing out a terminal or breaking the column switch entirely. . broke out a multi meter and here is what I know: 1. the fuse is good - continuity there - its a 15A fuse where the fuse box says it should be a 20A.. I'll get the correct one but for no that doesn't seem to be the problem (see point 2). 2. there is voltage across the head light fuse post ignition 3. however there is no power at main headlights terminal across all 4 headlight units 4. The low lights are working - they seem to have a separate circuit/power source... even with the connecters removed from the headlight until they still have power for the low beams. 5. there is power going to the dashboard pull out switch, at least for the low beams and buzzer for when the door is opened and lights are on.. 6. all other fuses are good bar the cigarette fuse which is gone, I'll replace but I don't think that will impact the headlights! 7. there is power to the other switches, dash lights, dash light dimmer is working correctly, indicators, hazards, etc etc all working.. 8. engine bay lamp is working fine too 9. there is continuity/circuit across the headlight unit terminal/bulbs.. so - there is power getting to the main light fuse post ignition.. that's for sure. From there the power goes to the pullout dash light switch which is working in the first position as the low beams come one (pre and post ignition).. I'm going to see if I can get the switch out and swap the terminals to see if that then places the main beams on the first potion and whether they work, which would mean the second position is the fault.. Another culprit is the dimmer switch, which seems to share the same circuit with the headlights - however, the switch itself seems to be working as the internal dash lights dim perfectly when used.. so eliminating that for now.. Any thoughts, let me know .. for now i.ve no transport after dark...

Hi All Id like to give the 620 some love this summer.. its pretty good but needs a few little finishing touches to really be 'perfect'.. one of my lovely hub caps got crushed after coming off the wheel and I'd like to find a replacement in as similar condition to the set as possible. They are all in excellent condition with no pitting or corrosion or dents - if anyone has one laying about in a garage, and would be willing to part with it - lets talk. Also - I noticed that the exterior trim on the drivers door, that the plastic/metal end piece is missing - it looks like it would have been riveted on at the factory.. im wondering if anyone might have an old door laying about with that part attached which they would be willing to sell. the interior is in nice condition generally however the carpets are the originals, and while nice to say they are original, they could do with replacing - are there any companies manufacturing carpet kits for 620 (king cabs)? also- both of the sun visions are missing their 'holders', the smaller plastic part which the visor is held in place by... again looking to find pair in nice condition if anyone has a spare set The clutch in the car works find but the release bearing has gone and it make a whirling, winding up noise when driving .. I spoke to a mechanic who said its find to drive with, its not damaging the trans or engine - but its something to get sorted - Im not at all familiar with what clutch sets are available for a 5 speed '79 620... if anyone has suggestions, please let me know. Worryingly, both my main beam lights have stopped working - main and highs - left and right.. they were both working find and then they weren't ... one went before the other but the second went soon after. My concern is that it might be the column stalk switch (from switching between high and main beams a lot on dark roads).. Im given all the wiring a look over, fuses etc, and nothing is out of the ordinary. . short of replacing both headlight units - Im wondering is there is a known common issue that others have experienced ? the low beams work perfectly. I've looked at wiring diagrams and checked against the car - all seems factory. Im going off now to buy a mulitmeter to see if there is power getting to the headlight at all.. but assuming there is power getting there - its either the no/off switch or the column high beam switch - and if the latter, Im pretty sure replacing that could be difficult.. love any and all input here as its my daily driver and I cant drive at night until this is sorted!! Lastly - this is not a major issue for now - but i notice that on full lock left or right there is a strange knocking sound coming from the wheel area, could be bushings or bearings or something - I dont have the tools to investigate.. but its something I'd like to investigate in time - again - if its bushings or tie rods or such, I can't imaging finding replacements being too simple - particularly in Europe.. I did drive the 620 from Ireland to Ibiza about 6 months ago - it never skipped a beat! hummed along the entire way.. I was majorly impressed by the little 2L engine.. smooth and you like.. its a great truck to have here, most of the roads are unpaved, boulders, dirt roads - its flies up them without any issues at all... if only I could get the cool air working..

yes, the low beams are working fine, as is the right turn signal, its only the main and fully beams and left turnsignal thats not working. the turn signal is going on but not flashing..

bumping in the hope someone can advise - many thanks!!!

All seems fine from the fuse box side of things - I swapped them out and no change to the lights... interestingly, the fuse diagram on the box cover/lid doesnt seem to match the fuse locations.. but either way, that doesnt seem to be the culprit. Given the fact that everything worked momentarily after the rain, it would point me towards a bad earth or ground - does anyone happen to know where earths/grounds for the headlights might be located?

HI all my truck is a 620 KC, 1979 - I've found set of hubcaps that look similar but the seller has them listed for a Datsun 1200 - anyone know if those will fit the 620?

thanks for the tip - its a 1979 620 KC I'll change the bulb in the side indicator but surely that wouldnt take out the high/main beams..

HI all My lights were all working perfectly until a few days ago and my full and main beams are now gone, along with the drivers side indicator (left turn) lights. The dash lights are also no longer working - and when I put the stalk to indicate left, the interior indicator just holds on (not flashing) I've checked all the obvious things like fuses and loose wires but all seems to be ok and I'm wondering if perhaps its in the switch on the steering column or something else entirely. dipped lights work. The emergency hazard work at the rear and passenger side but the front drivers side indicator doesn't flash.. we live in an areas off road, very bumpy and I'm hoping that something as come loose - but as mentioned, I didn't find anything off. One other point is that after heavy rain the other day, everything was back working but then stopped again, I assume once dried out - indicating a poor connection perhaps? any thoughts, tips, wiring diagrams etc would be a huge help! ian

HI all last week one of the hub caps flew off and ended up getting crushed under my wheel - its beyond saving, flattened. I'm hoping someone here might have a spare or know where they can be picked up. I live in Ibiza, Spain and its next to impossible to get any parts here or in Spain.. Also - i just noticed that one of the end silver bit of the exterior door trim is missing - again hoping to source an original part.. I cannot seem to upload pictures but the door trim piece is a silver rectangular end that covers the rivet that holds the door trim on, and the hub cap is a a original late 70s steel? cap - the ones are the truck were all in very good condition, no rusting or scratches.. i'm hoping to find one in matching condition.. thanks all Ian

yeah - this is what I think I'll do - the issue is that in Ireland we don't have the specialist shops that exist in the US, and with BREXIT, dealing with UK shops is a nightmare.. you don't know how lucky you have it in terms of car scene in the US - - I've a few old Porsches and its a ballache to get anything done here - whereas there are so many quality restoration and part fabricators over in California.. we have to spend twice the money on work half as good (and usually wait months for the work to be completed)