Flickering brake lights during warm up?
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Can you guys figure what is happening. It's about 7 PM in the evening and I decide to take my car out of the garage for a little warm up. I start the car, turn on the parking lights, and put it in reverse. I park it and exit the car. I walk to the back of the car and noticed the lights flickering ever so slightly. I thought to myself maybe my glasses are dirty. I look closely and noticed it again. The four break lights lightly flicker every 3 seconds or so. I look at the license plate bulbs and it dims slightly too.
Is it because the car is warming up? I told my friend to look at the lights and I lightly step on the gas. He said the flicker went away. When I let go, the flicker came back.
Is this normal or should I bring it in to the dealership? (Get a free car wash out of it)
Is it because the car is warming up? I told my friend to look at the lights and I lightly step on the gas. He said the flicker went away. When I let go, the flicker came back.
Is this normal or should I bring it in to the dealership? (Get a free car wash out of it)
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I can't think of any condition that would cause flickering of the brake lights. Sounds like a circuit problem and the dealer would be the one to best resolve it if under warrenty.
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Harrier,
My '02 RX does the same thing....from the day I brought it home. I also notice it the most in the tail lights and license plate lights. The most noticeable is when either the front or middle dome lights are on (Ithe headlights don't flicker because they are HID's). It only flickers when the engine is running. No flicker whatsoever when you turn off the engine. I brought it into the dealership and they said it was a normal occurance caused by the charging system. I thought it was a load of crap until I noticed the same flicker at night with the engine running on every single RX300 loaner I've had (at least 5 or 6 of them since they give me one just for an oil change since I don't want to hang around). If you do happen to ask the service dept, let me know what they say. Seems like a common thing with the 300's.
My '02 RX does the same thing....from the day I brought it home. I also notice it the most in the tail lights and license plate lights. The most noticeable is when either the front or middle dome lights are on (Ithe headlights don't flicker because they are HID's). It only flickers when the engine is running. No flicker whatsoever when you turn off the engine. I brought it into the dealership and they said it was a normal occurance caused by the charging system. I thought it was a load of crap until I noticed the same flicker at night with the engine running on every single RX300 loaner I've had (at least 5 or 6 of them since they give me one just for an oil change since I don't want to hang around). If you do happen to ask the service dept, let me know what they say. Seems like a common thing with the 300's.
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The tail lights/license plate lights flicker whenever the engine is running. Doesn't matter if it's warm or cold or if the car is in gear or not. The only time it stops is when you shut the engine and the alternator is not running.
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If I recall, the flickering is when the lights are off, that is they flicker on. And when they are on, the lights stay on ok.
I would start with the relay in the circuit and test from there. A weak relay might be the problem where the spring to open the relay ,to keep the lights off, is just a bit weak and allowing for intermittent contact.
Of course, tapping on the relay while flickering should show more or less as you tap, wiggle, etc. If not the relay, it may be an intermittent short in the control circuit fo rthe relay.
Also try swapping relays with another (identical part number of course).
I would start with the relay in the circuit and test from there. A weak relay might be the problem where the spring to open the relay ,to keep the lights off, is just a bit weak and allowing for intermittent contact.
Of course, tapping on the relay while flickering should show more or less as you tap, wiggle, etc. If not the relay, it may be an intermittent short in the control circuit fo rthe relay.
Also try swapping relays with another (identical part number of course).
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bringing this post from the dead... only had this 00 rx for a 1/2 year and just noticed it now. first cold start and i notice the shift console lights (PRNDL) are flickering, and then i look back and realize the rear talights are doing the same thing in the same pattern. it makes no difference whether the headlights are or on or just parking lights.
but after driving for awhile and things warm up, the flickering goes away.
what gives?
but after driving for awhile and things warm up, the flickering goes away.
what gives?
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Here is the best educated guess I have. Note it is a guess and not a fact.
Most of the charging of the battery happens right after the starting the engine. The bulbs in question (all elctrical load radio, sensors etc) and what ever is loading the alternator .. which is trying to push the electrons into the battery .. get the excess leftover from the alternator. Once the battery stops being a hog (builds up it lost voltage) it acts as a clamp and brings normalcy and all the electrical load sees steady voltage (no more flickering).
In nutshell, there is nothing wrong and for some this will not happen and for some it will happen in time.
If my reasoning is right, the dealership diagnosed it correctly for Steevr.
Salim
Most of the charging of the battery happens right after the starting the engine. The bulbs in question (all elctrical load radio, sensors etc) and what ever is loading the alternator .. which is trying to push the electrons into the battery .. get the excess leftover from the alternator. Once the battery stops being a hog (builds up it lost voltage) it acts as a clamp and brings normalcy and all the electrical load sees steady voltage (no more flickering).
In nutshell, there is nothing wrong and for some this will not happen and for some it will happen in time.
If my reasoning is right, the dealership diagnosed it correctly for Steevr.
Salim
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Anyone experienced any other problems - particularly in the radio/HVAC stack when this flicker began? We've had lots of reports of weird goings-on with the displays as the battery reaches the end of its service life.
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Originally Posted by Lil4X
:
Anyone experienced any other problems - particularly in the radio/HVAC stack when this flicker began? We've had lots of reports of weird goings-on with the displays as the battery reaches the end of its service life.![Uhh...](https://www.clublexus.com/forums/images/smilies/1387914497.gif)
Anyone experienced any other problems - particularly in the radio/HVAC stack when this flicker began? We've had lots of reports of weird goings-on with the displays as the battery reaches the end of its service life.
![Uhh...](https://www.clublexus.com/forums/images/smilies/1387914497.gif)
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The lights may not flicker but I'm thinking more about the clock resetting to 00:00, temp displays, etc. going all wonky. Those are the things that seem to presage battery failure.
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well my girlfriends 00 rx does this as well... its really annoying... but also like 1-2 times a month we will be coming up on a stop light and the car will die. then i can start it right up and its like nothing ever happend... its weird... she just gets pissed that my lexus doesn't have any problems lol... but i'm thinking its either battery or alternator... cause if i put the key in and turn accessories on everything is fine but as soon as i fire it up the lights begin to "strobe" so that is my assumptions
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The voltage regulator is build into the alternator.. I don't think it is available for replacement, but an electric/alternator shop has the testers necessary to load down the system and give you a good idea what the problem is. The parts are too expensive to just "shotgun" a fix. The battery, the alternator or a short in the system by another component. Could be one or a combination of the above. It's worth a diagnostic check.
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I recently posted a forum about a CEL and some other problems, I think it is still up, but anyways I had a similar problem. What happened was that when I would start the car, I noticed my front lights and all the other lights in my car (including the dash) were flickering (never bothered checking the brake lights). When I pressed down on the accelerator, they wouldn't flicker (check if the flickering stops while you are pushing on the gas). It turned out that my battery was fine (I recently put in a new one) and that the alternator was fine (it was still charging the battery), but the idle/speed control had failed. Apparently these things can go often and it is about 450 to get it replaced by the dealer, unless someone knows of a better way of doing it themselves.
I would check to see if your lights stop flickering when you press the gas, if it does, then head over to the dealer and have them read the codes. By pressing on the gas, he said that you were essentially overriding the idle speed control and then you were dumping gas. Just a thought. Good luck.
I would check to see if your lights stop flickering when you press the gas, if it does, then head over to the dealer and have them read the codes. By pressing on the gas, he said that you were essentially overriding the idle speed control and then you were dumping gas. Just a thought. Good luck.
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lawpurv... so your flickering was in conjunction with the CEL code? i have the flickering (albeit not consistently), but i do not have the CEL
i am bringing in the RX for service tomorrow. i already commented to the service advisor about it and he says he has not heard of this problem [EDIT: he has not had any complaints when he did a database search at the service counter when i was there in person], and that they would take a look at it and see if it is anything abvious and then call me back before taking action.
$450... ouch.
i am bringing in the RX for service tomorrow. i already commented to the service advisor about it and he says he has not heard of this problem [EDIT: he has not had any complaints when he did a database search at the service counter when i was there in person], and that they would take a look at it and see if it is anything abvious and then call me back before taking action.
$450... ouch.
Last edited by Benjamin T; 12-21-05 at 07:58 AM.