Re: Tail lights intermittently working
Check all the contacts at the bulbs and housings. Numerous times i had customers complain about weird issues after an installation with there tail lights. Ripped them out and 90% of the time if the bulb was still good, the contacts were about either rotted through or so dirty my DMM would only read about 3v.
Clean the contacts at the light, meter how much voltage your getting, you may need to find various points in the brake light lines to meter, if you have a slight break, or a corrosion issue, it would cause voltage drops. Think of it as turning your hose on with no nozzle, then standing on the hose, some water will still get through but not all, same principle.
It could also be deeper then you can see, my old jeep liberty was having issues with the cooling fan, it would barely run, sometimes not ever kick on. After metering the input side and metering the contacts directly, i would get 12v in but only 2v out. It was broken somewhere inside the connector and wasnt allowing enough voltage/amperage to run through it