fix for immobilizer issue? (3 Viewers)

[RobRed]

I'm not a fan of replacing a fuse with a jumper. The fuse exists to protect the circuit. Frankly I think I would want my Electronic Fuel Injection (EFI) fuse in tact.

Has anyone with this issue replaced the EFI relay? Perhaps it's so worn that the minute drop in voltage with a fuse in place is not closing the relay. That relay powers the fuel pump control and connects to the Main ECU of course.

 

[96crooser]

I'm not a fan of replacing a fuse with a jumper. The fuse exists to protect the circuit. Frankly I think I would want my Electronic Fuel Injection (EFI) fuse in tact.

Has anyone with this issue replaced the EFI relay? Perhaps it's so worn that the minute drop in voltage with a fuse in place is not closing the relay. That relay powers the fuel pump control and connects to the Main ECU of course.

Interesting, I also don't like replacing a fuse with a jumper, but it has worked. I think I will check into your theory.

 

[Bbuckner]

So today the immobiliser bug got me...2001 LC 235,000 miles. Changed the fuse to a new 25a...no change. The light on the center console still blinking, key in or out, still blinking and crank but no start. So I read where someone was sitting in his LC waiting for the wrecker listening to the radio and the blinking light went off and he was able to get started. This happened twice to him so even though it was 103 degrees I gave it a shot. So I'm setting there listening to the radio watching that light blink and decided I needed a little air, pushed the buttons to lower the two front windows and shazam the blinking light went off and the car started normally.

The 20amp fuse I removed was still good but it did show a slight discoloration on one of the legs. I think tomorrow I will order a new ECI relay and see if I can access those wires that go to the ECI fuse location and and bypass that socket with a new inline fuse.

I would really be interested in completely bypassing the anti-theft and immobiliser system. The LC and my Tundra appear to have the same engine, i wonder if anyone has figured how to make a LC engine run with Tundra ignition systems?

 

[ponytl]

I had the same Issue with my wifes 2001 LX470 you could tap on the efi relay inside the fuse box and it would start... that worked for about a year... then i built a new relay that sits inside the fuse box... just used a standard 15/20 amp relay like you might use on your off road lights... it has worked trouble free for 3 years....

 

[Bbuckner]

Update....i could not access the wires feeding that 20amp fuse so I'mgoing to have to settle with a new relay and just cleaning the contacts in the socket.

A friend of mine who has a Mercury Marine repair station thought that maybe when I hit the buttons to lower the windows that the extra current was all it took to bridge a dirty or coroded ground and once the circuirt was made it allowed the immobiliser sircuirt to make as well.....seemed to make sense but where to look?

 

[ponytl]

i built a new circuit with a new relay... if i get a minute I'll take some pictures and show how i did it... it's on my wifes LX might help someone out...

 

[Bbuckner]

Thanks, i am really interested in your solution. The bottom of that fuse box seems impossible to access. Thats where I hoped to splice into the wires feeding the 20 amp socket.

 

[GFL]

Bitten again and this time new fuse, jumper ... doesn't resolve the problem. Have ordered new fuse box/panel but find no info on removal/installation. Looking for a diagram and instructions. Any suggestions? Any tips on what not to do?

 

[El Cid]

Check the wiring of your 02 sensor as well, that appears to be the culprit in my situation.

 

[aljollano]

A paper clip saved the end of our vacation from Laredo to Austin TX.
Tomorrow I'm going to clean the connectors on the fuse box as much as I can.

 

[fengler]

Balls - you have them... I never would've shut that sucker off...

IM just reading through these threads and its funny you say that, because whenever i drive my 100 to a gas station or on a quick task, I always keep it running, just in case. I usually drive my highlander as my DD, but not knowing if the 100 will start is somewhat anxiety inducing!

 

[fengler]

I'm not a fan of replacing a fuse with a jumper. The fuse exists to protect the circuit. Frankly I think I would want my Electronic Fuel Injection (EFI) fuse in tact.

Has anyone with this issue replaced the EFI relay? Perhaps it's so worn that the minute drop in voltage with a fuse in place is not closing the relay. That relay powers the fuel pump control and connects to the Main ECU of course.

This is correct, a short circuit using a "jumper" is not a permanent solution. There is a reason circuit protection exists. As we all know, and i am currently experiencing, this is a common problem, but my advice would be to only use a jumper for emergencies. Maybe if in doubt use a tad bigger fuse and solder a few "button drops" onto the spades of the fuse for better contact. Source- Electro-mechanical engineer that has seen bad stuff happen to DAQ systems and ill-designed process control systems.

 

[fengler]

Also, if you guys really really want to make your own fuse/relay box, we usually buy parts from waytekwire.com for our trophy truck stuff.

 

[Bbuckner]

I attempted to access the bottom of my 100 fuse box so that I could splice into the wires that fed the 20a fuse in question. My intent was to replace that socket with an inline 20a fuse. I removed all the bolts holding it down and was able to get the bottom cover loose but could not get enough slack in the cabeling to even get a look at the bottom if the box. It looked like the best path from there would involve unpluggung cables that go through grommets heading toward the headlights in an attept to get enough slack, getting slack going the other way looked impossible. In the end I cut a sliver of an emory board and cleaned the contacts then sprayed everything with electrical contact cleaner. I wondered if di-electric grease would be beneficial.

I have a friend who troubleshoots lots of electrical problems on marine applications. When I told him about one guy getting the immobilizer to go off by turning on his radio and me doing the same thing plus operating the windows seemed to cause the fix, his thought was that that extra current flow bridged a fouled ground somewhere thus letting the immobilizer complete its circuirt as well.???....I'm still looking for a secure fix.

 

[96crooser]

This is correct, a short circuit using a "jumper" is not a permanent solution. There is a reason circuit protection exists. As we all know, and i am currently experiencing, this is a common problem, but my advice would be to only use a jumper for emergencies. Maybe if in doubt use a tad bigger fuse and solder a few "button drops" onto the spades of the fuse for better contact. Source- Electro-mechanical engineer that has seen bad stuff happen to DAQ systems and ill-designed process control systems.

I like the idea of adding width to the fuse, I may try that. As Bbuckner said, I also believe the cause is a bad ground. I also want to check out my O2 censor.

 

[GFL]

Installed fuse block assembly (82720-60023). Started right up so we will see if this fix lasts!! I had difficulty removing the old and installing the new. It took me at least seven hours. I think there are specialty tools that would make the task go faster.

 

[Bbuckner]

Congrats on the fix GFL. Did the old box reveal any apparent deficits that may have contributed to the immobilizer malfunction? If I have any more problems I would like to do the same as you. Do you have any advice about how to remove the fuse box?

 

[GFL]

I tried finding information on the internet without any success. There are sites that purport to offer pdf repair manuals ... BUT I tried accessing a couple of them and my anti malware software id'd them as trouble. They want credit card info to pay for the download and I was not willing to take the risk. One in particular looks like a Eastern European site that I suspect is a total scam. So I decided to order the part and work backwards from there to figure out how to remove and disassemble the fuse case assembly. The basic setup is straight forward and pretty simple if you have the replacement part in front of you. The problem is the case has a cover on the bottom that must first be removed and then the you can lift up the guts of the assembly and you have 11 connectors that have to be removed before the part comes out. This is a heavy wire harness that has very little slack so it is a slow process and you have little room to work. I have big hands that made this process slow. (My guess is that there are specialty tools that would make the job easier) I labeled all the different connectors to avoid mixing anything up but it turns out the plugs are all different and can fit in only one receiver. Replacing the 'bottom cover' is hard because there is so little room and the harness is so stiff it is hard to manipulate it into precisely the right spot. Doable but you can't be in a hurry. Hope that this helps. garry

 

[Bbuckner]

So you were able to unplug the harness on the bottom side of the fuse box? Do you remember how many plugs there were? I made it as far as getting the bottom cover loose but could not get enough slack to raise the fuse box enough to remove it. I'm going to get a mirror and have another look based on your success.....thanks.

 

[GFL]

Yes, after removing the four mounting bolts, you can lift the fuse block up starting on the engine side. You can lift it just enough to remove the first four 'plugs'. Then working my way through each row, I had to remove a total of 11 plugs. With each row you will be able to lift it a bit higher to get the next row. I needed a way to hold the assembly lifted up, so I used a bunji cord. You do not have enough hands and arms so you have to improvise! The plugs are a little tricky as you need to release the plastic locks by pushing in on the sides and pulling out at the same time. You have to work them back and forth and pull pretty hard to get them out. After the first four I got the hang of it and it got easier. g