PureDrifter

iTrader: (10)

only '97 and '98-00 model year cars had immobilizers. No removable chip is used to store the key codes, it is handled via encrypted software flashing.

Techmotion stated he had a '93, which therefore wouldn't have a problem.

ls400geek

All the more reason I will be extra careful recapping the ECU! Thanks.

LScowboyLS

did you recap your ECU yet? - results?

ls400geek

Not yet, still waiting for my boyfriend to help me take off the glove box I need to get behind there for the computer and to clear out the blower (whatever is inside it.. makes a clicking noise on startup sometimes).

LScowboyLS

the glovebox can be a bit of a pain, only because one or two of the fasteners is well hidden (one is actually behind a secret panel inside the lower glovebox - and I am not kidding!)

bees

I have a question. According to the quantity needed for the 98-00, there are two different caps needed for the 47uF.
Qty. 2 of 10μF - 50V
Qty. 2 of 47μF - 63V
Qty. 2 of 100μF - 10V
Qty. 1 of 220μF - 16V
Qty. 1 of 33μF - 35V
Qty. 1 of 47μF - 25V
Qty. 1 of 330μF - 35V

So can I replace all 3 47uF caps with any of the two recommended 47uF caps below?
the 47uF - 100V Panasonic FC EEU-FC2A470
the 47uF - 63V Panasonic FR EEU-FR1J470B

LScowboyLS

yes, you can always go higher in voltage, just make sure the capacitance is correct (47uf)

always check your ECU before ordering the capacitors, Nippon Denso occasionally varied a value, so my listing of what capacitors you need is typically accurate, but not a guarantee of the exact set your particular ECU will have in every single ECU variation.(for example, the TRAC models can be different, or California emissions, other countries besides USA, etc.)

LScowboyLS

A method for checking for a bad ECU courtesy of yamae:

TaffyK20si

Great thread. These symptoms of caps leaking could also be found true in say a MPX body module too, right? The only problem my LS is having is no power when the car isn't running.

LScowboyLS

I have not seen bad caps in a Multiplex Network Body Computer so far.

The Multiplex Network Body Computer handles the security horn, interior lights, trunk solenoid, head lights, wipers and etc.

I would check power and ground to it first, if the items above are the things that have lost power.

if you could remove the Multiplex Network Body Computer and photograph the inside clearly, and post the pics here, yamae or I could identify whether it contains the types of capacitors that are prone to failure

andrewmac

I don't really have any major problems with my LS400. However, the tachometer sometimes forgets to start moving, but with a swift Fonz-esque tap to the dashboard it comes back to life. The AC sometimes flashes and doesn't turn on. And when I put the foot down it feels like it takes a couple seconds to calculate what the hell I just did before actually taking off.

I'm not too confident tackling this on my own but I did come across this guy on craigslist:
http://losangeles.craigslist.org/lac...617457122.html

Has anyone ever used him? Seems like the price is reasonable.

PureDrifter

iTrader: (10)

never heard of them, more likely a company since their ad is all over craisglists throughout the country.

igotalexus

I am about to go pick up my 99 LS400 for the second time now from the shop due to unexplained issues. What has happened in the past is that the car will no longer crank. You can hear the engine and starter attempting to turn over, but it just won't happen. Both times now that the car has been in the shop as a result of this behavior, the mechanics have thought the worse. The engine is getting little to no compression, and the mechanics assume the timing belt is broken or worse. However, the vehicle while being diagnosed, goes through some reset process, and then begins cranking and running smoothly again. Subsequent attempts to get the vehicle to exhibit the bad behavior fails.

The first time it happened, I took the vehicle to an authorized Lexus dealer to have the ECM checked. They were unable to find anything wrong with it, but did find that the timing belt was off a few teeth. They corrected the problem and the car has run great for the last couple of months. Last week, I moved the vehicle down the driveway so the yard could be mowed. When I went back to crank it and return it to the carport, it wouldn't crank and thus the second trip to the mechanic. And like the first time, the car magically resets itself and starts working as expected. I should also add in case you're curious that the timing belt was replaced around 110K and the car has about 150K currently.

The car has had a few other odd issues in the past. Once, the A/C just stopped working and wouldn't respond at all. I thought the blower motor had gone out or something, but within a day or two, it started working again. The speedometer also sticks sometimes, but a slight whack on the dash will fix that. The steering wheel stopped automatically adjusting at one point, and then started working again.

So based on the behavior I've described, I'm leaning more towards an ECM problem, and am really considering replacing the capacitors before replacing the whole unit. I would love to hear what the members of this forum think, and if my problems seem to fall in to the ECM-problem area.

Thanks for the great info and any help you can provide.

PureDrifter

iTrader: (10)

'98-00 ECUs VERY rarely fail. while possible, the intermittent nature of what you're describing seems to point to a dying relay or sensor that keeps the engine from firing.

LScowboyLS

I have never seen a scenario other than dying ECU caps that has the combination of hard or impossible starting, A/C going out intermittently (A/C is controlled by ECU on LS400) and speedometer sticking.

do you ever have front defrost light flashing or air bag light coming on intermittently?

have you tried scanning the car for codes yourself (rather than the dealership doing it) like at autozone for example or with your own scanner?

I wouldn't say that and neither would yamae - they do fail *less* often (so far) than 92-97 models, but they still contain the same defective Nichicon PF (M) capacitors that are a common problem in earlier models.

besides, just like a timing belt, or a battery, electrolytic capacitors made by anyone have a certain lifetime, and beyond 12 years old is getting iffy at best

some of the smaller Nichicon PF series caps used in your ECU have a lifetime rating of only 2000 power-on hours, that means if a '98 model has had the ignition on for even on average 22 minutes a day (not hard to do) throughout its lifetime, it is already beyond it's rated life!