2000 LX 470 cranks but will NOT fire (1 Viewer)

[Shane Drummond]

Just had 2 spare keys made up, as when I purchased my LC only came with 1 key, the guy who programmed the 2 new keys said to me "don't try start with more than 1 key on the key ring, as the computer box will get corrupted trying to read 2 chips at once"

So basically if u have another key that will stop the red security light flashing on the center dash, use that as your master key, & find the thread that shows how to reprogram your other 2 keys back into the computer, also on YouTube

If that fails, get to a dealership or auto key programmer, they should have seen the same issues before

 

[barneyhyphen]

You're absolutely correct! Never remembered having any similar problem before but there it is in July '12.

Have to assume they're related problems but the last one obviously disappeared as soon as it arrived.

Wouldn't have thought the neutral safety switch would cause the immobilizer system to not recognize the key though, would it?

I did get two new key bodies, off the interweb, both which I had cut at the stealership and in to which I transferred all the old key internals. Those keys have performed flawlessly since July.

Neither of those keys nor the valet key are now recognized by the car. More fuel to the belief it's a car problem, not a key problem.

Is there a receiver ring around the ignition switch, which reads/recognizes the correct key transmitter? Could that be broken? Is there a fuse that protects that circuit?

BH

 

[spressomon]

AFAIK its the ECU that communicates with the key. A couple threads discussing whether the dealer can reprogram the master key/ECU...probably worth a call to your local Toyota dealer tomorrow if nothing else. Hopefully you don't have to buy a new ECU...

 

[barneyhyphen]

Thanks everyone's help today. Think I'm going to pop outside and take the steering column shroud off just to see if there are any obvious broken or lose wires in or around the ignition area.

Nothing better to do!

Will update soon.

BH

 

[barneyhyphen]

Ok. Black receiver "ring" now removed from around the ignition lock. Two pin socket on the back of the ring, attaching to a corresponding two hole plug/wire.

Thought I might be able to register a change in resistance, across the two pins when I introduced one of my keys to close proximity. No such luck!

Zero resistance (just like a very short piece of wire) from one pin to the other (red probe from OHM meter on one pin, black probe on the other) and it doesn't change when a key is held close by.

Not really sure how the above info helps BUT I'm going to assume, until I know better, that the equivalent of a continuous piece of wire in there is better that the alternative (infinite resistance) ie the equivalent of a broken wire!?

I'm viewing this "ring" as purely an antenna (not a switch) which perhaps, when energized, sends a signal to the key and receives some form of response back, which it then passes, through the plug/wire, to the ECU. The ECU then says, yes, this is a good key or no, this is not a good key.

Doesn't really help my plight right now but just trying to "thank this through".

Could a bad ECU ground be a culprit?

Throw me a bone someone.

BH

 

[Fitzgerald]

Wonder if there is a way to disable the immobilizer?

I'd hate to be out in the middle of nowhere and not be able to start my truck.

 

[arbetrader]

Did you physically "change" the EFI fuse? Does your immobilizer light continue to flash when key is inserted?

I had this issue on mine, my EFI fuse looked totally fine, I even cleaned it, but that did not do the truck. I replaced with a new one, and that took care of it. Must've been a hairline fracture or something I couldn't see.

Anyway, just a heads up to try actually replacing (if you haven't already), and I hope you get it figured out.

 

[barneyhyphen]

No, did not physically change the 20A EFI fuse but DID cast the hairy eyeball over it AND checked for/confirmed continuity with my trusty beeping volt/ohm meter.

Also took ECU relay out, took the cover off it and eyeballed it for burned contacts, THEN tripped it with my finger and checked/confirmed good continuity across HT (non-coil) side.

YES, car/key symbol remains flashing at key insertion, key position 2 AND whilst cranking.

Also took both 100A and 140A FL's out, cleaned all contacts, checked/confirmed continuity.

Last thing I did was to start focusing on the key/immobilizer/ECU system, by checking for lose/broken wires around the ignition switch and removing the black transponder ring that sits around the ignition lock.

All donations/suggestions gratefully accepted.

BH

 

[arbetrader]

In my scenario, the fuse looked physically fine; it worked fine 95% of the time. I cannot comment on your tests, and perhaps we're dealing with completely different issues; however I gotta say that my truck started fine 95% of the time, and I have to say that the symptoms were pretty much identical to what you are describing. The fuse tested fine on mine, however upon replacing it, it has not happened in months now, and my issues had progressively gotten worse over time the point of it finally happening every day until changed.

I hope you get it figured out.

 

[Travis351]

In my scenario, the fuse looked physically fine; it worked fine 95% of the time. I cannot comment on your tests, and perhaps we're dealing with completely different issues; however I gotta say that my truck started fine 95% of the time, and I have to say that the symptoms were pretty much identical to what you are describing. The fuse tested fine on mine, however upon replacing it, it has not happened in months now, and my issues had progressively gotten worse over time the point of it finally happening every day until changed.

I hope you get it figured out.

I can second this solution. Same issue here. Fuse had continuity when tested, replaced with spare in cover anyway...fired right up and it's been fine for over 2 years.

 

[APKhaos]

The coil on the ignition switch is an antenna. It sends an rf signal to the RFID chip in the key and reads back the chip code. Since your keys which all worked fine previously are now not being recognized (red key light) the coil or its contacts may be the problem. Far as I know the red key light is controlled by the RFID identification and nothing else so the immobilizer (ignition and fuel pump cutoff) will be active until the key is recognized. I'd go for replacing the coil.

 

[barneyhyphen]

Thank you so much for all the great input, very much appreciated.

Actually ordered the transponder ring this morning but it won't be in until the morning. P/N 89782-33020 for those interested. Lexus and Toyota # identical. $ 27 from Toy, $ 36 from Lex. What a surprise!

I WILL be CHANGING the 20A EFI fuse this afternoon, with the original transponder ring fitted back in, worth a try.

I think, if the above garners no positive results, next, I will be removing the fuse box so as to clean thoroughly underneath.

Will report back asap.

BH

 

[barneyhyphen]

Ok Boys & Girls, brief history........

I've been working on all sorts of cars & trucks for 40 years. Learned THREE things,

1) Look at the basics first

2) Look at the basics AGAIN

3) You will keep learning

POP QUIZ TIME.......

Look carefully at the fuse shown in the attached two pictures

Q. Is the fuse shown in the picture GOOD or BAD?

HINT...It looks GOOD and it checks out for continuity.

Do you have your answer yet?

I have been battling this problem for 5-6 hours and have been told to CHANGE THE FUSE. Did I change the fuse? NO, I eyeballed it twice, cleaned the socket in to which it fits once AND confirmed continuity with my OHM meter.

Have however just CHANGED THE FUSE and, guess what....Problem solved.

Thank you to everyone on this one but SPECIAL kudos to ARBETRADER & TRAVIS 351. 20 cent fix!!!!!!

 

[Travis351]

I feel like a jerk on a soap box when I harp on that fuse right out of the gate in these threads anymore, but I've learned to mistrust those smaller spade fuses in general. A friend with a Chevy from the early 90s carries a full selection and has to regularly replace fuses that look fine just to keep everything going.

 

[barneyhyphen]

Keep on preaching it. You was on da muny my son. Good job, thanks.

BH

 

[Supra88]

We've all been in that predicament and can empathize with how you felt. Glad you were able to resolve it. This is truly a great site.

 

[Wasatch Jay]

Barney,

I'm glad you got it fixed and it turned out to be a cheap fix at that.

I must confess I've been following the thread and I was impressed with your tenacity and with all the suggestions. There are some really smart folks on here.

 

[barneyhyphen]

Thanks. i work on the assumption that 99.9% of the time, whatever the problem (mechanical/electrical) IT WILL NOT BEAT ME and I WILL EVENTUALLY FIGURE IT OUT (just takes a little collective help sometimes!)

BH

 

[APKhaos]

Great stuff. Good to hear it was a nice simple fix. I'm storing this one away for reference

 

[barneyhyphen]

I think what we (I) take away from this is that we need to start at the simple end of the problem and do WHATEVER it takes to confirm good results at EVERY stage, BEFORE we move down the line to more complicated fixes.

Sometimes I think we (Certainly me) are too quick checking the basics, not doing a thorugh job, before we rule out the fuse/wire/relay, somehow WANTING the problem to be more involved than it actually is?!

Thanks again all the input.

This is a fine forum. We also have 3 BMW's so I spend a lot of time on E46fanatics and bimmerfest. Very similar knowledge banks to that found here.

BH