I know if the handbrake is very slightly up, it disables the DRL's, as there are a couple of mirco switches for various functions to let it know it is released. Check the DRL resistor on the passengerside strut tower for an open wire or resistor grid, using an ohmmeter(should have less than 3 ohms IIRC). Also, check the 7.5A DRL No.1 fuse, which is by the battery. Post back your results.
I checked the handbrake and both fuses in the passenger side fuse box, both 7.5A and 30A and they still looked good. I forgot to mention that I did the old school Joe-Z DRL Mod way back in the day when I first got my IS. I may need to clean the wire and harness.
Okay, well from this point comes troubleshooting. You'll need a voltmeter and set it to read less than over 12 vdc. Take out the dimmer relay and check accross terminals 1&2 for 12vdc when the car ignition is on and handbrake down. If so, then wiring/connection issue. If not, problem with DRL main or switch. That relay turns on the power for the DRL's. If there was an issue with the handbrake switch, then we can simulate that if need be, by grounding the wire.
Also, does both high beams come on or just one. The DRL circuit appears to be in series during low power because I just pulled one connector and they both went out.
Got everything working again. I took out the DRL High Output Relay and cleaned out both sides of the DRL Module harness. I also put the e-brake down and everything is working now. I'm going to check in the morning to make sure everything is still working. Thanks for all your help.
Ah, glad to hear you got it. I wondered if you use the e brake a lot because of the DRL microswitch. Anyways, may have been a connection you cleaned as well. Job well done:approve:
Hi Jason,
I'm getting similar issues with my DRL's from what the original post reported. I have a '01 IS300. I cleaned out both sides of my DRL module harness, it still doesn't work. I checked both fuses and they appear fine. My highbeams work fine. Just my daytimes don't work.
You mention about the DRL microswitch in terms of the e brake. I don't use my e brake much and usually just leave it down. I tried pull it up and down to see if it would help and nothing.
Any suggestions on what I should check next? I'm a newbie.
If they worked at some point, verify the resistor box on the passenger strut tower has a good connection. At this point you would need a voltmeter to check of its the DRL module or something else. When the car is running, parking brake down, check to see if you have power to fuse 10A H-LP L UPPR to chassis ground. If you don't have power then your DRL module isn't turning the Dimmer relay in.
When On, the DRL's are in series, so if you have power above working, verify that both bulbs work during high beams. If so, go to the relay in the front passenger corner in bay to a black box marked DRL relay. Check for a reduced voltage to chassis ground on the red/white stripe wire with harness pulled off the relay. If you have power, then that DRL relay is bad or there is a bad connection at the DRL resistor. The white with black stripe wire on the DRL resistor goes directly to constant ground, so the problem would then be an open resistor or bad relay, as mentioned.
One other check to see if the DRL relay is good is to use an ohmmeter and pull the relay(front right corner of car). With relay pulled, check pin5 to pin3. It's were the red and red/white stripe wires go, respectively. Contact should read closed or continuity. If not, replace relay. If that reads ok, check DRL resistor for open. No open circuit, DRL module is most likely bad.
My problem is the DRL/ High Beam work fine, but when i turn light on, the DRL on passenger side doesn't work, the one on driver side is still on! All the fuse look fine!
Do you guys know what happen?
Hey so I just got these new leds for my high beams, they work when I turn on my high beams but they don’t work as my daytime running lights, that’s the main reason I got them. For white drl, can someone help? All my fuses are good. Thank you
There is no way to make them work at half power. Only certain LED will dim. They are ether on or not. DRL system drops voltage down. If you do a search and read. You will find this and what a few have used for LED's.
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