So in my 82 fj60, after a led Cluster upgrade, when I stand on the brake pedal, both turn signals on dash light up at about 15% brightness.(have not checked outside)
I assumed it was a bad ground on the brake light circuit feeding back through the turn signal circuit seeking a ground.
I cleaned up the a pillar grounds, no change.
So I performed a couple tests.
I found that when I press the brake the GY and GB wires into the plug behind the dash both get power.
With hazard on instead of brakes both GB and GY blink. with right turn on GY blinks, left GB blinks, verifying I have the right circuits at the plug.
Tested with brake pressed
GY on
GB on
Under the theory that this was due to a bad ground, I went to the tail lights and added a known good ground to both stop lamps.
Jump wire from the clip where the WB wire connects to back of brake light fixture. Connect to a nearby ground. Test. Both light up.
Then connect straight to the negative terminal on the battery and retest.
Both light up.
Here is my good ground setup.
Gator clip with black wire on tab with WB wire on outer stop lamp housing
Red wire to big clip is connecting straight to neg on battery
Other end of Black test lead also to same tab on right stop lamp. Theirby Connecting the grounds on both tail lights directly to neg on battery.
At this point, both are directly connected to neg on battery.
Diagram shows bo ground directly on stop switch, this is only ground in system... so connecting at lamp socket should bypass all grounds. In theory...
So if the issue is, a faulty ground, when I press the brake an neither should light up any more right?
When pressing the brake pedal, both the GY and GB still lit up.
That means I have a short somewhere right? Not a faulty ground? Did I perform the test correctly?
Since both the GB and GY wires have power when brakes pedal pressed, the short is probably on the common GW wire somewhere after the flasher relay(because it's not blinking) ?
Or it's to both the GB and GY wires?
Here are my references. If you care enough to check my work.
Closeups of parts of diagram I think are relevant, to make process easy as I can.
Wiring & harness diagram(upside down, sorry)
Close up of Brake circuit(sideway, sorry)
Close up of turn circuit
Turn signal plug pin out diagram(how I know GY and GB at plug are turn signals hot.
Thanks, any help is appreciated, I know this is a big post.
I assumed it was a bad ground on the brake light circuit feeding back through the turn signal circuit seeking a ground.
I cleaned up the a pillar grounds, no change.
So I performed a couple tests.
I found that when I press the brake the GY and GB wires into the plug behind the dash both get power.
With hazard on instead of brakes both GB and GY blink. with right turn on GY blinks, left GB blinks, verifying I have the right circuits at the plug.
Tested with brake pressed
GY on
GB on
Under the theory that this was due to a bad ground, I went to the tail lights and added a known good ground to both stop lamps.
Jump wire from the clip where the WB wire connects to back of brake light fixture. Connect to a nearby ground. Test. Both light up.
Then connect straight to the negative terminal on the battery and retest.
Both light up.
Here is my good ground setup.
Gator clip with black wire on tab with WB wire on outer stop lamp housing
Red wire to big clip is connecting straight to neg on battery
Other end of Black test lead also to same tab on right stop lamp. Theirby Connecting the grounds on both tail lights directly to neg on battery.
At this point, both are directly connected to neg on battery.
Diagram shows bo ground directly on stop switch, this is only ground in system... so connecting at lamp socket should bypass all grounds. In theory...
So if the issue is, a faulty ground, when I press the brake an neither should light up any more right?
When pressing the brake pedal, both the GY and GB still lit up.
That means I have a short somewhere right? Not a faulty ground? Did I perform the test correctly?
Since both the GB and GY wires have power when brakes pedal pressed, the short is probably on the common GW wire somewhere after the flasher relay(because it's not blinking) ?
Or it's to both the GB and GY wires?
Here are my references. If you care enough to check my work.
Closeups of parts of diagram I think are relevant, to make process easy as I can.
Wiring & harness diagram(upside down, sorry)
Close up of Brake circuit(sideway, sorry)
Close up of turn circuit
Turn signal plug pin out diagram(how I know GY and GB at plug are turn signals hot.
Thanks, any help is appreciated, I know this is a big post.
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