Hi. I have a 2010 Subaru Forester with 146,000 miles with only the third upper brake light functioning. Both the left and rights brake won’t light up when brakes are applied. I’ve replaced the bulbs, tested the bulbs and they work. I’ve swap fuses and tried a new brake light switch with the same results. I’ve checked the sockets, pulled up the back seat to see if anything looked pinched, corroded or something obvious. Besides pulling apart the entire interior to fish for something what could it be? I’m stumped.
Thanks,
Michael
Well on your Subaru it's likely those subpar tail light wiring harnesses and you can confirm it with a test light.
Remove the brake light bulb socket from the tail light housing.
Remove the brake light bulb.
The socket has 2 contacts in it for the 2 contacts on the bulb.
1 contract will have Power when the brake pedal is pushed.
1 contact will be Ground.
So use the test light to determine which is missing.(one certainly is)
Then, disconnect the 3 bulb harness from its connector and repeat the drill with the test light on the "input connector".
When the brake is pushed, 1 contact in that connector should have power.
There should also be a ground contact in there.
If you have power and ground at that "input connector" to the tail light connector, but not at the brake light bulb socket, you'll have to replace that 3 bulb harness. (about $25 from Subaru)
Saga continues, used a new tail light wiring harness to no avail. I’m thinking a possible issue with the wiring harness somewhere
Does the bulb socket have a ground wire mounted to the chassis? Maybe the ground wire came off or is corroded.
