If you read my previous posts, my instrument panel has been flickering. Well, Magnussen has traced the problem to a bad circuit board. To install a new board with the correct mileage readout, is $1000!

Man, that's a lot of dough for one circuit board. It's a very intermittent problem right now. Should I just live with it until the thing completely dies? Or is there another solution?

HELP!!!

 

If something flickers , but still works
I usually assume that something is loose.
I'd look for a connector problem/power source
before dropping $1K.

A electrical diagram would help alot, of course.
That all I can advise.

 

Thanks mlevk. That's what I guessed too. But the dealer said that it was a problem internal to the circuit board.

It's a $1000 for the board with the correct mileage, 300 less with one with zero mileage readout. Obviously, there would be a detrimental effect on the value of the car should I get an odemeter with incorrect mileage.

If anyone else has any ideas, I would greatly appreciate it.

 

I have to agree with mlevk. One way to find out for sure would be to pay attention to if it does it only when the car is moving. If it still does it sitting in the driveway not moving then the chances are greater that you have a bad board.

It's not typical for electronics to perform intermittently, however they can in rare instances. The cause of the intermittent operation is usually overcome by current and that part of the circuitry is destroyed making the failure permenant.

My initial thought is a bad board, but not the circuitry. I think it is more likely a bad or cold solder joint which can be affected by heat and cold.

See if the dash lights flicker while the car is just sitting in the driveway. If they do then your problem is most likely on the board or a connection to the board.

If your dash lights flicker only when your driving and experiencing bumps, turns etc. then it more likely a connection or wiring problem.

See if you can reach up under the dash and move some wires around. See if it flickerss.

$1,000 is a lot of money. I'd try other stuff first.

 

Thanks Additude. I think you've come very close to the problem. The problem is worst when the car is cold. When you start it up, the dash is sometimes dark. Then as the car warms up the needles will flicker and come on, followed by the background flickering and then coming on. While this has happened a time or two while the car was moving, generally it is when the vehicle is cold.

The dealer diagnosed it as a bad circuit board and gave me the part number. Problem is, dealers are loathe to finding loose wires, bad solder joints, etc. To them, often it's just simpler to replace the entire part.

My problem is I 'm not technically qualified to take apart the dash much less fool around with electronics. If there were some kind of auto service shop that was good at these kinds of things, that would be ideal. Otherwise, I might be stuck getting a new board.

 

The Lex,

Those are symptoms of cold solder. It's possible it could be a board connection also.

Being as your not familiar with electronics, PCB's and solder maybe you could pull it and take it to a TV repair shop. Someone who knows how to solder and what to look for.

But you might have a difficult time finding someone. Check the Yellow Pages......maybe you can find someone there under electronics repair, etc.

I'd do it for you if you lived close to me. I know what I am looking for. I worked on cards for 10 years with IBM.

 

Additude, thanks for all the info. I really appreciate it. Can an electronics repair place tell by looking, what is bad on the board?

The other thing that is weird is that the dealer wants $300 to have the board programmed with the correct odometer reading. Somehow this board controls the odo also. This suggests the thing has some sort of flash memory?

 

A good solder joint is shiney and reflects light well. A cold solder joint looks hazy. But, if all the joints on the board look sorta hazy then it is just the solder used.

By taking the board and holding it an an angle to the light you can check the solder connections. It's possible you don't have a complete solder on one lead of a component or even no solder at all and the lead is just making contact with the inside of the barrel.

It probably takes a trained eye, but you'd look for hazy solder joints on the underside of the card, cracked solder, no solder, partial solder and worst case is that solder didn't fill the barrel (Hole in the card the component lead fits through) and the joints need to be touched up by a solder iron.

If you'll be working on the borad, you'll have to make sure you have a grounded (3 prong) solder iron, a static free and grounded work station and that your grounded.

These are all just precautions to prevent static discharge from damamging any electronic components on the card. What you basically want to do it make sure you, the board, the work surface and the soldering iron are all at the same potential so current cannot pass between each of these.

Like I said, I did it for 10 years working with everything from transistors, TTL packages, SMT, BGA and some of that stuff is micro-mini and I had to use a 7x stereo microscope to work on it.

If it is there I know I could find it, I know I can tell you how to find it, but unless you have done it before you'll have a problem.

$300 to program it might seem expensive, which of course it is, but the programing machine and software is also very expensive. I would bet the dealer has to send it off to the factory to have it done or even repaired. I can see a dealer having a car key programmer unit on site, but not an odometer mileage programmer.

Factories are expensive to run. It might take one employee a total of 2-3 hours to receive the unit, unpackage it, get it to the tester, test and program it, get it back to shipping, package and ship it.

Look at it this way. I had the main board go out on my commercial embroidery machine. It would have cost me $4,800 to replace it and $1,200 to repair it. That board is by far less complicated than the MoBo in your computer. $1,000 sucks, so did my $1,200.

Keep us posted if you find the problem or just decide to replace it.

 

Thanks Additude, for those detailed and complete responses. You're a wealth of information. Now I have to decide whether to try the repair or just have it replaced. I'll let you and all the rest of the gang here know what happens. Have a great day!

 

I have an extra SC cluster board. I bought it for the speedometer.
I have a guy that will program any miles you want for $400 That way there is no record at Lexus.. (Service history can be a ***** sometimes, when it comes to selling.)

The cluster works fine and the mileage works good also.

Let me know if you would like to buy this one. I will sell it for 100 bucks.. if you want it.

THe programming will be around 400 maybe less I need to contact my guy to make sure..

Email me if you are interested at wscottwilliams@insightbb.com

C-ya,
Scott

 

Hi... i got the same problem...it is definitely to do with cold weather.... the instrument panel cluster and the whole of the centre console lighting is linked.

U will see after a while it just refuses to come on at all when the temp is cold. At night the whole centre console is not lit re backlighting for switchgear.

Then after an hour or so drive through warming the air temperature the centre console switchgear will light up first...then needles on dash will flicker and then as the circuit is established the whole dash will display as normal. Its funny watching the fuel gauge jump widely up and down as the circuit is established !!!! Not funny as all winter i have not been able to see instruments !!!!...but now coming back slowly when warm...


What i am interested in is the actual part number that you were quoted for by the dealer......this will help me a lot as the dealers here will not touch my car as it is an import direct from Japan.

Thank you

 

Thanks for the responses!

Scott, I don't know if the circuit board for an SC400 is the same as the one for a '93 LS400. Thanks for the offer. If the part numbers match, I might be interested. See my answer immediatly following to Yin for part #. Thanks again.

Yin, that's it! Those are the EXACT symptoms I am experiencing! It's quite frustrating isn't it? The part number is #83247-5A050RP. I was told that the RP part of the number is vitally important as this is for a reprogrammed odometer board reading the correct miles. If you have a odo that reads different than actual mileage, the car will take a huge hit on resale value. Who besides the Lexus dealer are you going to have perform the work? Do you know of any source for a discounted part or perhaps even getting it from Japan itself?

 

yep.....actually can you just check one more thing....whats the part number without it being reprogrammed ???


i may ship one direct from japan need to cross reference part number that is set to 0 if it is cheaper.......

will keep u posted

thnx agian

 

Yin, I don't have the PN without the reprogramming but the dealer did tell me that the RP on the end of the serial # is the part that specifies it to be reprogrammed. So I suspect that the correct serial number w/o reprog is the whole series minus the RP part.


Please post what you find out re: prices etc. If the part is significantly cheaper than the dealer here, perhaps we might get a deal if we buy two?

 

Hi,
I have also got this same problem. I have a 1994 LS400 with 80K miles on it. The problem started last year as a sporadic problem when the car was cold. Now, especially since it is winter, the dash stays dark for at least an hour while driving. This makes it very difficult to determine how much gas is in the car. Also, when the console is dark, the odometer does not register the mileage, not that I'm bothered too much by that. I would be very interested in getting a replacement board - maybe we can get a better price with more of us ordering the cards together?