Hello, all. Let me start my first post with the obligatory "I searched, but..." Seriously, I've spent a while trying to figure this one out, so I'll apologize now if I overlooked something obvious on the site.
I've owned a number of MN12 T-Birds over the years--two SCs and two 4.6 cars. This past weekend I picked up my first Mark VIII, a 98 LSC. It's pretty nice for its age, but like any 20+ year old car, it has a few problems. One is that the CHMSL (third brake light) isn't working. I admit I'm not an expert on electrical stuff, but here's what I've figured out so far:
-The left and right brake lights work, but I understand they run through a different system, not directly from the brake switch.
-The ballast for the neon light is definitely bad. It was unplugged, and when I plugged it in, it flickered once, so I ordered a new ballast from ebay. Right now it's unplugged again.
-The brake fuse (#32) is good. No problems shifting the car into park.
-The brake switch has continuity across the contacts when the brake pedal is pressed.
-The connector that plugs into the brake switch measures at 12 volts.
-With the brake pedal pressed, I'm getting 12 volts to the connector in the trunk that goes to the third brake light.
-The bulb harness and bulbs appear to be good. I removed it from the car, hooked it to a 9V battery and both bulbs came on.
So it seems to me it should be working, but as I said, I'm no expert. Is having a bad ballast, or leaving the trunk neon unplugged, in and of itself causing the third brake light to not work?
Thanks for your attention and your time.
-
I've owned a number of MN12 T-Birds over the years--two SCs and two 4.6 cars. This past weekend I picked up my first Mark VIII, a 98 LSC. It's pretty nice for its age, but like any 20+ year old car, it has a few problems. One is that the CHMSL (third brake light) isn't working. I admit I'm not an expert on electrical stuff, but here's what I've figured out so far:
-The left and right brake lights work, but I understand they run through a different system, not directly from the brake switch.
-The ballast for the neon light is definitely bad. It was unplugged, and when I plugged it in, it flickered once, so I ordered a new ballast from ebay. Right now it's unplugged again.
-The brake fuse (#32) is good. No problems shifting the car into park.
-The brake switch has continuity across the contacts when the brake pedal is pressed.
-The connector that plugs into the brake switch measures at 12 volts.
-With the brake pedal pressed, I'm getting 12 volts to the connector in the trunk that goes to the third brake light.
-The bulb harness and bulbs appear to be good. I removed it from the car, hooked it to a 9V battery and both bulbs came on.
So it seems to me it should be working, but as I said, I'm no expert. Is having a bad ballast, or leaving the trunk neon unplugged, in and of itself causing the third brake light to not work?
Thanks for your attention and your time.
-
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