My immobilizer fix (1 Viewer)

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Hey Team P1600 -

Looking for some advice....

I have the '03 LX470 with an immobilizer bypass.

I recently installed a Group 49 Duracell battery from Sams, I really liked how it was bigger and more CCA's, etc, etc, even tho it wasn't the recommended battery.

After installing, the check engine light came on, later diagnosed as the P1600/ECM/Battery/EFI Fuse issue.

I cleared the code (like a dozen times) but it keeps coming back.

After reading through all the posts here (also like a dozen times and coloring all the photos I printed out), I think I need the same fix as @lexs470 had, which seems to be suppling 12V to Block E, which is currently blank on my rig.

Where should I rig the power from for the E terminal?

My hypothesis is that the 'stronger/newer' battery finished burning through the faulty fuse block taking out Terminal E which wasn't a problem previously. Is this plausible?

It doesn't look like @lexs470 will respond.

Do you really have '03 LX470? I am asking because this is not a common problem for 2003+ models. If you have a 1998-2002 model, then you are the 2nd person that I know of, who got P1600 after doing some electrical work to the vehicle. I use the 12V from the fuse holder that is used to power the relay, for the power to "E".
 
It doesn't look like @lexs470 will respond.

Do you really have '03 LX470? I am asking because this is not a common problem for 2003+ models. If you have a 1998-2002 model, then you are the 2nd person that I know of, who got P1600 after doing some electrical work to the vehicle. I use the 12V from the fuse holder that is used to power the relay, for the power to "E".
You are correct, my Insurance actually says 2002!
 
pOk guys - just had this issue on my 2001 LX470. I tried the EFI relay replacement before finding this post. The fuse on the input side was actually a little melted so I replaced it and it works fine now, but I am assuming it will get worse. One question - if the input side of the fuse is my problem, then couldn’t I just jump it from one of the two un-used fuse locations with the “kit”. I put a meter on both open fuse locations and they are switched with the ignition. I assume this would work, but would appreciate any feedback or suggestions.

I am planning on using the factory relay.

Lastly - I have read the thread and reviewed all of the pictures and is everyone using 10 and 12 gauge wire on this? It seems a little overkill and that 14 should be fine looking at the factory wiring harness.
Thanks
 
pOk guys - just had this issue on my 2001 LX470. I tried the EFI relay replacement before finding this post. The fuse on the input side was actually a little melted so I replaced it and it works fine now, but I am assuming it will get worse. One question - if the input side of the fuse is my problem, then couldn’t I just jump it from one of the two un-used fuse locations with the “kit”. I put a meter on both open fuse locations and they are switched with the ignition. I assume this would work, but would appreciate any feedback or suggestions.

I am planning on using the factory relay.

Lastly - I have read the thread and reviewed all of the pictures and is everyone using 10 and 12 gauge wire on this? It seems a little overkill and that 14 should be fine looking at the factory wiring harness.
Thanks

You want a supply that is not switched. I used 10 gauge fuse holder and 12 gauge wires.
 
Just got the notification for this thread. I got the power straight from the battery with an inline fuse.
 
Perhaps another immobilizer fix option....??

Pair a 25 and 30 amp fuse to the EFI fuse slot and connect it to the spare port in the adjacent box.

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I am curious. Did this work?

I am not sure. I just bought this 2000 LX and happen to notice the electrical artwork. I am curious myself if it is an immobilizer fix. Perhaps so, why else would it be there, I wonder.
 
Just did the this fix.
I couldn't get it to work using the A terminal of the 20 amp fuse. So I ran a line to the positive terminal of the battery.
Initial testing is positive, will see what a few days of teen driving stress testing will prove out.

I'd like to permanently fix with a new fuse box. My cover shows part number 82677-60022 which is a Toyota part number.
Any idea on what the correct Toyota part number would be for the fuse box considering this is a 2000 LX? I know many of the parts between the two are the same, however not all.

I called Lexus and they quoted $704.32 for part number 82720-60023 which also shows on Toyota Parts - Genuine OEM Toyota Parts and Accessories Online - https://www.toyotapartsdeal.com/ as a Toyota BLOCK ASSY, ENGINE ROOM JUNCTION for $493 retail price $704.32. Looks like I may have found a match.
 
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Just did the this fix.
I couldn't get it to work using the A terminal of the 20 amp fuse. So I ran a line to the positive terminal of the battery.
Initial testing is positive, will see what a few days of teen driving stress testing will prove out.

I'd like to permanently fix with a new fuse box. My cover shows part number 82677-60022 which is a Toyota part number.
Any idea on what the correct Toyota part number would be for the fuse box considering this is a 2000 LX? I know many of the parts between the two are the same, however not all.

You have a permanent fix already. The wire to the battery is your permanent fix.
 
'98 LX470 here and I'm not sure if I have this issue or not.


Here is a pic of my fuse box. PO said he didn't know anything about it when I asked but I have doubts.


Based on the pic, did a previous owner try to do the same thing? Looks like there's a wire going from radio to EFI fuse.


I removed the wire a few weeks ago and had issues starting the truck but I believe it's only from a broken key issue (separate issue?) From my knowledge, I think the broken key was the only issue but not sure if I also have a fuse box issue or fuel injection issue

Should I be worried about my fuse box or connection to fuel injection?

20210306_154525.jpg
 
I am really trying to follow this fuse immobilizer working thing as best I can,, but am a bit confused on this whole wiring thing. Can someone put it in simple terms? 😅

Is OP still on here? Can I buy the kit from you?
 
I am really trying to follow this fuse immobilizer working thing as best I can,, but am a bit confused on this whole wiring thing. Can someone put it in simple terms? 😅

Is OP still on here? Can I buy the kit from you?

Put your LX in isolation for 14 days then try to start it, you don't have any problem if it starts :):)

Seriously, if you don't have intermittent crank and no start issue then you don't have this problem.

If you have crank and no start then check to see if you have blinking security light while engine cranks. The security light is located next to the clock display in center console.

If you have blinking security light while engine cranks, then follow troubleshooting instructions in post #51.

Yes, I am still here. Please send me a PM if you would like to buy the kit.
 
'98 LX470 here and I'm not sure if I have this issue or not.


Here is a pic of my fuse box. PO said he didn't know anything about it when I asked but I have doubts.


Based on the pic, did a previous owner try to do the same thing? Looks like there's a wire going from radio to EFI fuse.


I removed the wire a few weeks ago and had issues starting the truck but I believe it's only from a broken key issue (separate issue?) From my knowledge, I think the broken key was the only issue but not sure if I also have a fuse box issue or fuel injection issue

Should I be worried about my fuse box or connection to fuel injection?

20210306_154525-jpg.2617358

Hard to say what problem previous owner was trying to solve. The radio circuit could be helping in fixing problem in EFI circuit or vice versa. If you want to find out what it does, drive it without that wire.
 
Worked! The terminal A is either pushed down in there, or corroded and half gone. I had to really push the connector down in there for it to stay. I hope it doesn't pop out. I will rig up something to keep it in place. Unless, there is somewhere else I can put it in place of terminal A?? Anyway, thanks for the info on this!!

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You can run the fuse holder to battery positive post if terminal A is not reliable.
Ok, so terminal A is just the power source? Sorry, I am the Village Idiot here :) Thanks for the quick response.
 

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