My high beams both work but one running light is off how do I fix it? and I already tried pulling the plug under the battery and that did not turn the running light off

 

Welcome to Club Lexus.

There are relays that switch the 2 high beam filaments in series to give you DRL. Headlights are different circuit. If no work has been done, then most likely the culprit is the relay. You would need circuit diagram to trace which relay or dig through how to disable DRL on first gen RX.

Salim

 

So I assume each light has its own relay?

 

The configuration can be pretty weird and you really need circuit diagram. Engineers are smart and to protect some strange unexpected behavior they throw in things for safety measure. There may be more than 1 relay involved.

Conceptually one higbeam (- end instead of being grounded for regular operation) feeds the + of the second high beam bulb. [+/- are being used to differentiate the two ends of the bulb].

Since you are getting 1 high beam as DRL ... I suspect you are getting full brightness implying the relay is not flipping over to bring the other bulb in circuit.


Salim