All my crazy Lexus issues SOLVED!! (ECU-leaking capacitor)
#496
LS400 1998 UCF20 european version.
I had the transmission problem since I have bought the car 4 years ago.
As I said earlier, I have changed capacitors and the problem got solved.
Yesterday I checked the old capacitors, and only one had visual defects. I´m not a specialist, but check out the 3 bubbles on the top.
I had the transmission problem since I have bought the car 4 years ago.
As I said earlier, I have changed capacitors and the problem got solved.
Yesterday I checked the old capacitors, and only one had visual defects. I´m not a specialist, but check out the 3 bubbles on the top.
The coating is done to avoid to absorb the moisture. It is often the case that bubbles were made on the parts which have longer time constant to cool down.
#497
I bet those 3 bubbles are not soft nor wet. If so, those bubbles must be made when the surface coating for the board was applied at the factory.
The coating is done to avoid to absorb the moisture. It is often the case that bubbles were made on the parts which have longer time constant to cool down.
The coating is done to avoid to absorb the moisture. It is often the case that bubbles were made on the parts which have longer time constant to cool down.
never the less, new capacitors solved my problem !
#498
Those capacitors can't be judged by eyes. As I investigate, the problem starts more than 1 year prior to the leakage as the ESR increases and the capacitance decreases. Usually only very sensitive people can notice the performance change. Then one day, the person is upset having a serious problem when totally leaked.
Those Nichicon capacitors end the life far before the engine worn out. It is a smart idea to change those capacitors before that as a preventive measure in accordance with this written by LScowboyLS.
Last edited by Yamae; 10-09-13 at 03:51 AM. Reason: Add the deatail and the suggestion
#499
Thread Starter
Lexus Champion
LS400 1998 UCF20 european version.
I had the transmission problem since I have bought the car 4 years ago.
As I said earlier, I have changed capacitors and the problem got solved.
Yesterday I checked the old capacitors, and only one had visual defects. I´m not a specialist, but check out the 3 bubbles on the top.
I had the transmission problem since I have bought the car 4 years ago.
As I said earlier, I have changed capacitors and the problem got solved.
Yesterday I checked the old capacitors, and only one had visual defects. I´m not a specialist, but check out the 3 bubbles on the top.
If it is not too much trouble, can you post pics of all of the capacitors that came out of this ECU, especially showing the markings?
#500
Good or bad news, depends how it take it, but that one is really a BP capacitor. So now I need to change one capacitor, although I didnt notice anything wrong with the car (but I didnt drive much too).
one more time special THANKS goes to electronic expert LScowboyLS for the help !!
one more time special THANKS goes to electronic expert LScowboyLS for the help !!
#501
Thread Starter
Lexus Champion
a bipolar (BP) capacitor is a very special type and has no polarity - everyone who has a 98 and newer LS please take note that one of the three 47uf capacitors you will be ordering is this special type and will have to be ordered separately.
I have clarified this in the links section of post #1 of this thread.
I have clarified this in the links section of post #1 of this thread.
#502
a bipolar (BP) capacitor is a very special type and has no polarity - everyone who has a 98 and newer LS please take note that one of the three 47uf capacitors you will be ordering is this special type and will have to be ordered separately.
I have clarified this in the links section of post #1 of this thread.
I have clarified this in the links section of post #1 of this thread.
47uF - 63V - PF(M) - 3 pcs,
47uF - 25V - BP - 1 pc.
#503
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From: florida
#504
Thread Starter
Lexus Champion
a nice fix is just to buy one of the many bargain replacement LCD's for this on ebay, seems like they are about $40 and you will have to solder about 100 pins
they did it when the LS400 was on British TV show wheeler dealers
they did it when the LS400 was on British TV show wheeler dealers
#506
Thread Starter
Lexus Champion
the problem with a used replacement for the climate control for $75 is that its LCD screen is of the same vintage and design and could fail at any time, the replacement ones you solder in are brand new and a newer technology.
#507
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From: florida
Thank you for all the helpful advice. I did get one of the updated replacement LCD screens and did the patch. However, something very odd occurred - my display, while nicely lit up and showing the temperature, was cycling through the hours without stopping! It was as if the hour button was depressed permanently! I took the thing apart and found that the face-heating process to release the old LCD had caused some of the glue to spread into the openings for two of the three clock-setting buttons and caused them to jam, thus freaking out the clock!!! Just wanted to post this as a caution to would be repairers that if this happens, it is most likely not the soldering job, it could be, but check for the buttons sticking in the openings first. I used a small triangular file to clean up the openings and the problem was solved. Panicked me because I thought I had done everything very meticulously, even fixing the ripped up trace and testing all connections before putting it back together, and had no idea of where to go for troubleshooting the symptoms!!!
Also, unlike the ECU capacitor repair it is very easy to rip up the traces with this repair since if you are using needle-nose pliers to lift the LCD lead you could very easily rip them; wait unitl the solder is actually melted (a split second for a 30 watt iron) or you will rip up the trace and then have to repair it!!! It happened to me, and I thought I was being very, very careful HA!
Another thing that I think would be helpful - this time for ECU fixers - the capacitor pins on the other side of the boards where the solder is are usually bent outward then soldered. I found that it helped prevent messing up the board and solder tabs if the pins were straightened as soon as the solder melted and BEFORE attempting to get them out of the board. If they are not straightened there is a good possibility of ripping up the solder tab, and maybe even the trace on the other side with the bent capacitor pins - sort of a hooking effect!
Hope this helps, and thanks again, all!
Last edited by fsuguy; 10-14-13 at 02:44 PM.
#508
The one I bought was advertised as having the LCD panel replaced with a new (updated) one.
I think that it was true, because it has been working perfectly for two years or more.
However, I am sure that at least some are just pulled and sold as is.
As with anything on e-bay, caveat emptor.
I think that it was true, because it has been working perfectly for two years or more.
However, I am sure that at least some are just pulled and sold as is.
As with anything on e-bay, caveat emptor.
#509
Yes Sir I did as you said and ordered the Caps from Digikey
You know between You and Yamae ya'll must have an extremely high Chiropractor bill from all the beating and banging you get from the multiple " Pats on da Back " I've had my Caps sitting on my work bench since around July but after my daughter was ' T-Boned " ( Passenger side luckily ) in her Continental I had to either purchase another car or put the ECU back together with fingers crossed. The no-brainer had me installing my $ 6.00 worth of parts and ...... SHA-ZAM !! An amazing transformation took place. As with many of the posts I see on this thread, the results were no different. My 1997 LS400 is purring like the day I bought it. My only letdown is that the speed-o is reading around 10 mph lower than actual speed. I'm wondering if it has something to do with the 30 ga. wire that I soldiered around the broken trace strips that occurred from the caps leaking and probably my cleaning of the board a little to hard in that area. I didn't keep the length the same as the tracers I by-passed but didn't see where that would matter other than the " not perfect in observation " that no-one would see. ( As in the pic below ) ( I had zero on my ohm meter with the wire I used ) Anyway, Thank You Guys a thousand times over as this experience has enlightened me in ways you can not imagine.
Oh yea, the speed-o deal . . . Any thoughts ??