i have a '90 240 and the brake lights have gone out. the light on the dash isn't coming on to tell me they're not working, and i checked the fuses just to be sure. do the brake lights have a transformer under the hood like the headlights do? could that be the problem? thanks.

same thing happened to my 89 wagon last week. with a little advice from rule308 and a 17mm open end , i was able to remove switch at pedal. whatever fiddling i did to it, same switch now works. not an expensive part if it has to be replaced. tony h on march 30 of this year has good post on testing brake switch while in car. as usual, the wire going to the light in liftgate is broken in my wagon, so if i don't see sensor light in dash come on when i brake, i know something's up with lights/switch.


thems the brakes
gary c.

re: "...the brake lights have gone out. the light on the dash isn't coming on to tell me they're not working, and i checked the fuses just to be sure. do the brake lights have a transformer under the hood like the headlights do?..."

Hi.
There is no transformer, neither for headlights nor for taillights. The headlights do have a "relay", however -- this is to handle the headlights' higher amperages and save wear on the switch, something unnecessary for mere brakelights.

As for your problem, it could be that BOTH brake lights have burned out. The lights do have a "lights out" warning system, but it's based on making left-to-right side comparisons of amps, so that if a bulb on one side is burned out, the difference will signal a warning (btw, using different brand bulbs can sometimes give a false warning if they use very different filaments, so it's always good to replace bulbs in matched pairs). On the other hand, if both bulbs have burned out, there's no warning because the electrical flow (zero) is equal on both sides.

I would start investigating by checking (with a VOM, or at least a test light) to see if 12 volts is going to your brake lights' bulbs. If not, and assuming you've checked the fuses carefully (ceramics are tricky) and have no corrosion problems, I'd next check the brake light switch (unnecessary if your center, rear window brake light is working, which at least confirms a working switch).

Good luck.

i assumed that it wasn't the bulbs simply burning out because the center light is out also. i'll start fiddling around. thanks.

The voltage to the brake lights goes from fuse to pedal switch to Bulb Failure Sensor, then goes on two separate circuits to the lights on each side (and the center light).

The bulb failure sensor is the most likely suspect, IMO. With a meter or test light, you can check for voltage (brake pedal depressed a bit) in by back-probing the Blue/Red wire. If voltage is there, check the outputs on the Yellow and Yellow/Gray wires. Input but no output = bad BFS.

If no BFS input voltage, suspect the pedal switch or bcorroded fuse contacts.
--
Bruce Young
'93 940-NA (current) — 240s (one V8) — 140s — 122s — since '63.

your screwed. No, but if it is not something simple this is a very hard to diagnose problem. Start in the back and check for voltage. somtimes the printed boards in 240s burn out. You may have lost a ground somewhere. I had a similar problem and I wired from the alternator to the actuator under the brake pedel to the brake lights


Check for voltage.