Headlamp control module intermittent fault

[Hector2021]

Up until a week ago i had no problems whatsoever with my headlamps. They always popped up when asked and closed again once done with. Suddenly and recently this was not the case. Sometimes they would illuminate and rise, sometimes they would just illuminate and not rise. Occasionally once they did rise they either wouldnt go down, or just the offside one would close leaving the nearside raised.
First investigation was to remove the headlamp delay module from behind the driver side dash to see if the connections to this were dicky,(they werent) but i had failed to check the orientation that i had removed it in, so had to work blind lining the blade connectors up with the socket.
Next check was continuity between the motor output pins of the Headlamp control module on the bulkhead and the motor connectors. This proved intact.
Following that i checked the voltages at the module on the five pin connector. I got 12v at pins B and E and 12v at pins A and C when the dip beam was either turned on via the main switch or the flash stalk. The earth to pin D was also sound. Occasionally however the relay would pick when the flash stalk was pulled and then drop after 2 seconds as it should. I had disconnected the motor connector but i did get 12v on pins A & B and C & D of the motor connector.
Both dip beam bulbs were working, as were both main beam bulbs.
I figured that the control module had gone duff so considered the path of obtaining a replacement. This proved quite tricky and from one ebay source, not without risk. They wanted £105 including postage, plus exchange of my module for a used one sourced from another car (Not reserviced). This was almost surely going to be older than mine since my car is a 95, so probably nearing the end of its own life.
From there i did what i should have done several steps ago and did a forum search for the same symptoms. One post suggested cracks in the solder joints of the connector strips on the pcb. Difficult to spot with a naked eye as they would be very tiny cracks, but with the aid of a loupe they should be visible if this is the problem.
Sure enough and to my relief there were two clear cracks across the soldered joints on pins A and B of the power connector strip. With my eyes i would not have spotted them without a loupe.
A quick resolder later and a few more touch ups to other components that looked a bit thin on solder, the module is now back up and running perfectly as it was previously.
Result being just what i like most - No cost and existing piece of kit repaired and back in use.
I have to say though that the pcb does look a bit of a cheaply produced effort with rather flakey looking etching and copper tracks.
Interestingly the sticker on the rear of the module stated "Replace - Do not repair". A sure fire green light to ignore it and at least try and "Repair - before replace".

[Saltire]

Well done - I had similar issues with mine, although in my case I needed a couple of replacement components from the very helpful Tuga2112 of this parish. I did find I needed a very sharp scalpel, though, to cut through the “Replace - Do Not Repair” sticker

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[Tuga2112]

i didnt read the whole post.

unfortunately lately im running a bit short of time with life getting in the way and work being more demanding that normal.

i saw a wall of text and skipped to the end and saw that you fixed it.. WELL DONE.

again. this headlamp motors information needs to be aggregated and compressed.. another wiki page im sure... and i guess between 3 or 4 different people we could put a pretty compreensive article.

i have been trying to get people who replace their units to send me the old one. but everyone wants to old to broken electronics instead of passing them to someone who will attempt to fix.
i have told some of these people that if i get a spare one fixed. i can swap it with whoever has the next one broken and charge a fraction of the ongoing rates. but no one wants to be the first to volunteer their scrap electronics.

if anyone has any idea how to reach the broader audience with that offer id be all hears. but i wouldnt be offering this as a club thing because i cannot offer any guarantees as some units are non-repairable and although my repair is still going string after 5 years, that doesnt mean the next one will last that long

BTWthis is the kind of thing you need to find the solder cracks