I have a 240 that when I put the lights on bright sometimes the will go off as soon as I hit the switch. And tonight they went off while driving. Any Help with this?

In my experience (happened twice now) this is caused by a failing headlight switch. On the pre-86 240's the headlight switch carries ALL the electric current for the lights, and the contacts eventually burn/oxidize from the load and develop resistance. When you switch on high beams (4 lights on your car) the switch won't carry the extra current and the lights fail. Eventually it gets bad enough that the low beams also become intermittent.

It could be the beam switching relay as BC suggested, but the next time the lights go out, try wiggling the light switch - not On-Off, just rotate the knob back and forth a little. If that restores the lights you need a new switch.
--
Bob (son's 81-244GL B21F, dtr's 83-244DL B23F, 'my' 94-944 B230FD; plus grocery-getter Dodge minivan, hobbycar 77 MGB, and numerous old motorcycles)

From what you say, it could be a failing stepping relay.

Do the high-beam / low-beam switching with engine not running and hood up. You should hear that relay giving a good solid "clunk" with every pull of the stalk.

You might just pull the connector off the relay and replace it, that will clear off any accumulated oxidation.

240s have used that relay from beginning to 1993, easy to find several in a boneyard.

That relay is the only one in the headlight circuit.

Good Luck,

Bob

:>)