99 Tahoe low beams always on, turn off when switch is in on position?

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Joxe435

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I bought a new master light switch hoping it was the problem, but it wasnt the problem. Im not complaining because all of my switches are new now. Either way, when I start the Tahoe, the low beams(hids) kick on no matter what. When I actually need them on, if I put the switch in the "all lights on position" it completely over rides my lights. If i put the switch in the middle, I have low beams but cant flash lights. Any help is appretiated. Thanks in advance.
 

east302

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Probably the multifunction (turn signal) switch. Sometimes the wires can get damaged, especially if the tilt wheel is slammed up and down a lot.

I had the same issue a few months ago and that was the fix.


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Joxe435

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I actually changed the multi switch first because my hazards button was missing. I changed the light switch next, of course after checking all my fuses. for now, I just use the switch all the way on during the day to keep my headlights off. Then at night i drop the switch to instrument lights only and my headlights come on as well. it sucks. I cant flash my lights right now.
 

east302

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Diagnostics for a 1998, maybe it will help...

Low beam headlamps inoperative:

562BA58B-FF5C-45A5-88F6-86A56F86CF68_zps4qrggf2h.gif



F551639D-F209-4FAC-AB08-94EC02CA1956_zpsgxrv6pim.gif

03E134A2-FED7-41D1-AB48-22A1BE90EDB2_zpswqhazbxw.gif


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Kenny D

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Your low beams come on with the switch off because it is your daytime run lights, do you have the little green indicator on your cluster when the lights are on?
 

east302

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Kenny brings up a good point. The DRL module will energize the coil in the DRL relay to close the contact and activate the low beams when the headlight switch is off.

When the headlight switch is on, it looks like you get power from the headlight switch to the dimmer switch via the DRL module, then through the open DRL relay contact and on to the headlamps.

If there are no obviously damaged wires, you'd just need to check each component for voltage in and out to see where the disconnect is.

Could be the DRL module not cooperating or the relay contact not opening back up. If I was going to throw a part at it, I'd start with the DRL relay on the convenience center:

77182D06-E7F6-44CD-8B07-A16E0CBFF425_zpsftoyje1i.gif

Question: with the headlamp switch in the "on" position, do your high beams work?

01BBF86C-34A0-4FAE-AC9F-35E55D07827E_zps1qfjt6u9.gif

E6288938-0BEF-4CC0-82EE-39127284494E_zpsfqrimh5q.gif

79BD733B-14AA-4A03-9503-86E5483B8CA3_zpsl0lnvpyb.gif


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BladeMaker

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Engaging the hand brake should disable DRL. I engage the foot pedal about 1 "click" and it doesn't turn on the parking brake warning light or engage the parking brake but it does disable DRL and turn the DRL light on the cluster off.
I don't know if this applies to you, but if your handbrake is sometimes on when you get out to look at your lights, this may affect what you are perceiving as your lights being off or on mysteriously.
 

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