I have a 1991 Eunos - the cigarette lighter works and creates a glowing lighter coil. When I plug in a usb charger adapter into the cigarette lighter socket it barely illuminates the LED “on” light and will not supply enough power to a sat-nav or mp3 player to use/charge them. Any ideas what the problem is?
Disconnect your battery so that you don’t cause a short, get your self a sharp terminal screw driver and scrape the rust/debris from the central probe in the lighter socket.
As an ex-smoker i know when cigarettes are lit they leave filth on the plug coil which then damages the socket pos probe.
Then a light squirt with WD40 should sort it.
Cigar/cigarette lighter sockets were never designed to accept power accessories.The cigar lighter element is powered by the bi-metal “claw” that holds it around its perimeter.If you look down the socket you will see a contact stud or rivet.This is what an accessory device needs to contact ,usually not very well.I would suggest you change the lighter socket for a proper power socket.Something like this will do the job; https://www.ebay.co.uk/itm/12volt-Power-Socket-20Amp-rated/381672424122?epid=1294569958&hash=item58dd7302ba:g:M-4AAOSwY45UTqMT