iridebmx

iTrader: (6)

Basically what the title says. I just recently changed my alternator and recharged my battery to see if either would correct this issue before I came to the forum. But no it didn't.

Every time I turn on my side blinkers my lights twitch or "dim" every time they go on. What could be causing this? I haven't spent any money so far with the alternator having a lifetime warranty and ending up being bad and the battery charge being free as well.

Would a grounding kit maybe help? Or just a few 8 gauge wires here and there?

mikef

iTrader: (3)

mine does it, even my other cars, i just thought it was normal to me

SC400slide

iTrader: (11)

I contacted a certified Lexus dealership employee and asked if this was the ECU. He said no, it's probably a grounding issue. Out of all of my issues, this was the only one not fixable by simply rebuilding the ECU. All old cars have it. My guess is that the grounding points ned cleaning, or replacing.

jpw

My car has been doing this for as long as I remember (had it for about 7 years). I wonder if it could be a blinker switch issue?

On a recent long trip, I noticed another pattern. I'd turn on the blinkers and the dash lights would dim. Then I'd turn the blinkers on again after just a second or two - this time no dim.

If I waited at least about 15 seconds or so and turned them back on, the lights would dim, but not as long as I did it again a few seconds after ...

Hatchy400

Some questions I need you to answer(with all lights on):
Does any other lights dim(ie headlights/marker lights)
Do the lights dim when brake pedal is pressed.
Do the lights dim under load(ie car is in drive, foot is on brake)
Do the lights dim only when your blinker is on.
Do the lights dim with your 4way on.
Do the lights become BRIGHT if you increase the RPMs.

The first thing you need to do is check your voltage drop from Bat.+ to starter and Bat.- to engine. If you have any more then a .2 drop your leads need to be replaced. Also make sure your battery leads don't have corrosion build up on them and that they are tight.

Two things usually cause this it's either poor chassis ground or corrosion/poor connection to bulb. The first and easiest I would start with is check all your bulbs(tails,corners,fogs,exe.), make sure nothing is corroded or connected poorly(if bulb is working but looks burnt recommend replace). Also check the connectors as well, as they can become dry and corroded(with light on wiggle the wires around/pull in and out GENTLY!!!).

If that does not fix the issue then I would suggest grounding the Battery, Alt., and Engine with 8 gauge wire or larger.

iridebmx

iTrader: (6)

Just bought a new battery as my car died on me today. im thinking my "new" alternator was faulty as well. will buy a multimeter tomorrow.

with all lights on and all electronics on in the car:
-if i press the brakes nothing dims
-if i repeatedly press the brakes at a fast pace the car will idle lower then pick right back up when I stop.
-lights only dim when blinker is on
-lights do not dim with emergency lights on
-lights stay the same when increase in rpm

one thing i think i should mention, my corner lights are both out.... not sure if that would cause it to happen? i dislike them but would buy new ones if it could potentially resolve my problems.

does anyone know what voltage my battery leads should be at when at a warm idle?

turbodremz

iTrader: (18)

Add or make a grounding kit. That solved this issue with my SC years ago. Best $45 Ive ever spent.

Battery to body
Battery to block
Head to body
Block to body
Transmission to body

gerrb

iTrader: (34)

Hey buddy, how have you been ? got your 6 speed in ?

Based on what you wrote above (what I boldened and made bigger) and the diagram below , this will be my guess .

I doubt it is your battery , alternator or ground . The hazard (emergency) basically uses same ground, battery and alternator and you are not experiencing the dimming of lights when that Emergency switch is on.

Looking at the diagram , the only thing I can see on the diagram is the flasher relay. Some flasher relays have IC / transistors or what not. Am not too sure with that of the SC. Looks to me that when you turn the signal switch left or right , something is shorted that draws more current and consequently dims your headlights.

Based on the diagram , I would suspect something on the flasher relay... the other circuitry around it is common and is used by the emergency switch (hazard) also for which should be good since you don't experience the dimming when hazard switch is on. The L & R signal switch connects only to the hazard switch, ground and flasher relay as seen on the diagram. So, I believe there is something on that flasher relay causing the problem.

if you want to enlarge the picture , click on it and will bring you to photobucket , click the + sign on the lower right side , then click it again on the picture that comes out and then click it once more and will give you a really enlarged diagram.

just my $0.02 .. can be something else.

Hatchy400

^^^It's Most Likely Your Relay. I Would Still Recommend Putting In Some Bulbs In Your Corner. If It Where A Ground Issue Your Lights Would Dim When The 4Way Is on.

Lexman4375

To answer iridebmxs' question about battery voltage. At cold crank, your battery voltage will read 12.4 Once you start up, your volts will jump between 14 and 14.6. Mind you that's with no headlights,wipers etc running,just your belt and pulleys. Once the car warms up at a soft idle, the volts will dwindle down to around 12.5. I hope this was helpful

iridebmx

iTrader: (6)

6 speed is in and has been doing great. Completed it on Christmas day actually. Also drove the car last weekend from Mississippi to Colorado without a problem.... until now that is.

So what was my little worry about dimming lights has now left me stranded twice, today being #2. I really think my 'new' re-manufactured alternator is bad. There are other culprits though that I did not mention prior.

My power steering actually went out on my trip up to Colorado and basically emptied the fluid all over the older alternator.(reason I warrantied for a new one) I've noticed the wires from the a headlight actually run directly to the alternator... Tomorrow I plan to check all wires for any remaining fluid on them.

Right now I am experiencing a very fast battery drain. Bought a cheapo multimeter and as the car idles the voltages drops at a steady rate and with car off the battery recovers. Brand new AGM battery began its idle at 12.7 then gradually made its way lower and lower into the 10's then I shut the car off. #1 suspect, faulty alternator. Unfortunately my crappy multimeter refuses to check amperage unless I'd check to see if there is a draw somewhere killing my alternator while the cars off.


right now i am considering buying another sc400 and just swapping parts over... this one has caused me problems to long. should've done it a long time ago

Lexman4375

Don't give up on your baby so fast. You have too much invested at this point. It definitely sounds like the alternator. Take it to autozone,they will test it for you to see if the alternator is bad or not, then make your decision accordingly on what to do. A donor car isn't bad to have on hand for parts etc

gerrb

iTrader: (34)

Well, I guess if your battery is draining so fast , it is an alternator issue. That battery voltage should stay constant while the engine is up and running. It is supposed to be replenishing back to the battery what is used by the different components in the car.

IF the car has no rusts and mechanically sound, maybe you just have to go through your wiring gremlins so to avoid a lot of work swapping stuff and save you money.

iridebmx

iTrader: (6)

So the gremlin is gone!

Went back through and cleaned all the connections and added 3 0-gauge wires. Along with another battery recharge.
-alternator (+) to battery (+)
-alternator 'bracket' to chassis
-battery (-) to strut tower

im still bitter about my car though. its on craigslist haha