[WeCruzn69]

69 Chevelle... Headlights work just fine, but when I turn on the high beams, both low and high beams come on - on the driver side, but on the passenger side, the high beam head light turns on as should, but the low beam light turns off. When I turn the high beams off, both low beams work as they should.

Is this an issue with the passenger side low beam head light, or wire issue?

 

[69SS454]

Replace that head light lamp. The high beam filament is burnt out.

 

[NickeyChevelle]

A simple thing would be to swap the headlight bulbs side to side. If the issue follows the bulbs you'll need to buy a replacement headlamp. If the issue remains on the passenger side then it's a wiring issue.

 

[WeCruzn69]

Thanks, guys. Will do.

 

[DUTCH MAX HEADWORK]

If it's a burned out bulb, replace them both so they will be equal color and brightness. I would put Halogen bulbs in. Best bang for the buck and increased light output. I would put halogens in the high beams too.

If originality is your game, they make reproductions that look like the original T3 headlights.T3 headlight bulbs for 1969 Chevelle - Google Search I see that you left headlight is a T3 bulb.

 

[lg1969]

69 Chevelle... Headlights work just fine, but when I turn on the high beams, both low and high beams come on - on the driver side, but on the passenger side, the high beam head light turns on as should, but the low beam light turns off. When I turn the high beams off, both low beams work as they should.

Is this an issue with the passenger side low beam head light, or wire issue?

View attachment 699248 View attachment 699249

Replace the headlight, it's burntout

 

[japete92]

You say: "... but when I turn on the high beams, both low and high beams come on - on the driver side, but on the passenger side, the high beam head light turns on as should, but the low beam light turns off...."

From your pic, the HIGH beam light is OFF (the inboard bulb). The low beam (outer bulb) is illuminated.

The 'outer bulbs' are dual filament (one for high, and one for low). Their connector has three prongs. The filament 'in use' is determined by the switch (high or low beam). Only one filament at a time is in use. This is why those bulbs are always illuminated whenever the headlight switch is 'on' (regardless of 'high', or 'low' beam selection).

The inboard high beam connector has just two prongs. The inboard bulbs are monofilament (high beam ONLY). It's either 'on' when high beam is selected, or 'off' when low beams are selected.

Depending on the accuracy of your initial statement (you mixed up your 'high' and 'low' beams), you may have something wired incorrectly.

Pete

 

[oldcutlass]

As the others said above it's probably a bad lamp and a simple voltage check will confirm this at the plug.

 

[WeCruzn69]

If it's a burned out bulb, replace them both so they will be equal color and brightness. I would put Halogen bulbs in. Best bang for the buck and increased light output. I would put halogens in the high beams too.

If originality is your game, they make reproductions that look like the original T3 headlights.T3 headlight bulbs for 1969 Chevelle - Google Search I see that you left headlight is a T3 bulb.

They are all T3 bulbs. I will take your advice and replace them as sets. I think I will put halogens in. Thank you.

 

[WeCruzn69]

You say: "... but when I turn on the high beams, both low and high beams come on - on the driver side, but on the passenger side, the high beam head light turns on as should, but the low beam light turns off...."

From your pic, the HIGH beam light is OFF (the inboard bulb). The low beam (outer bulb) is illuminated.

The 'outer bulbs' are dual filament (one for high, and one for low). Their connector has three prongs. The filament 'in use' is determined by the switch (high or low beam). Only one filament at a time is in use. This is why those bulbs are always illuminated whenever the headlight switch is 'on' (regardless of 'high', or 'low' beam selection).

The inboard high beam connector has just two prongs. The inboard bulbs are monofilament (high beam ONLY). It's either 'on' when high beam is selected, or 'off' when low beams are selected.

Depending on the accuracy of your initial statement (you mixed up your 'high' and 'low' beams), you may have something wired incorrectly.

Pete

Thanks, Pete. There are actually two pictures posted. Maybe you're just seeing the one. There is one picture with the high beams (inner bulbs) off with the low beams (outer bulbs) illuminated and then the other picture shows the high beams (inner bulbs) on and the passenger side low beam (outer light) off.

 

[WeCruzn69]

Well... I just finished swapping both left and right low beam bulbs to see if the problem would transfer to the other side... now all the lights work as they should. Go figure. LoL Must have been a bad connection on the passenger side where it plugs into the bulb. Will see how long this lasts, but thank you all for the help and advice with this!

 

[japete92]

Thanks, Pete. There are actually two pictures posted. Maybe you're just seeing the one. There is one picture with the high beams (inner bulbs) off with the low beams (outer bulbs) illuminated and then the other picture shows the high beams (inner bulbs) on and the passenger side low beam (outer light) off.

Glad to hear swapping the bulbs 'fixed' the problem.

I did just focus on one pic. But, because of the 'fix', and because of the nature of bulbs on passenger side prior malfunction, suggest you inspect/clean the connectors (especially on the passenger side) at some time. Replace if necessary.

The system works the way I explained it. Your prior symptoms (even looking at both pics) did not appear to be a bulb only issue to me.

Pete